Have I really just been gay the entire time? It's all very confusing

Right so where to start? I'll try not to make this too long because ultimately you guys will have heard all this before, so apologies if you're sick of it!

Ok so I'm a 20-year-old male and I've only been questioning my sexuality for about 6 months, although I'm getting more and more obsessed with and consumed by it as time goes on.
I think it started when I was out for drinks with friends, one of whom I'd visited at their university a few months earlier. Looking back on that visit I was in a really good, confident place (or maybe it just seems like I was compared with how I feel now). I remember just not being afraid of talking to anyone and despite having my heart broken a month or so earlier by my ex girlfriend I was feeling really happy. I was gonna get drunk, go to a club and try to get laid. The usual aim.
So anyway, going back to this night a few months later, the friend who I'd visited said really casually "hey, my friends at uni really liked you. They thought you were gay at first but then they realized you weren't." Of course I just laughed, but inside I had this awful feeling, like my stomach had just been twisted. I guess a part of me kind of thought "whoa, is that how I come across when I'm happy and just being myself?"
I couldn't get it to leave my mind. What if I was gay but had just been repressing it the whole time? On the whole I guess I'm a pretty insecure, sensitive person, but maybe that's just because I've been subconsciously hiding my true colours my whole life? At first I just did my best to ignore it and carry on as usual, going out, trying to hook up with girls etc. But this time it was different; every time it didn't go well with a girl, as in they weren't too keen on me or I didn't get a text back the next day, run of the mill knock-backs in the dating game, there it was again; "what if they can sense that you're gay, and they're put off by your lack of masculinity?" (please note at this point I do not see gay men as less masculine, I'm just talking stereotypes).
It kept getting worse, and as it did I managed to create this paradox for myself- my confidence was deteriorating because of this obsession, affecting my confidence with women, therefore becoming less appealing, therefore getting more rejections, and therefore questioning myself more frequently.
As this vicious cycle continued, and frankly continues, I began to question everything. I spend hours on the internet looking up signs of homosexuality and seeing if they relate to me, as well as seeing whether I can relate to gay or other confused people's stories. A lot of the time I can. I started experimenting with gay porn which, and I guess this could prove a crucial part of the story, I do enjoy and in fact a lot of the time excites me more than straight/lesbian porn. I do still mostly watch the latter and I enjoy it, but I guess I might well be kidding myself, as not doing so might be some kind of unwanted admission to myself.
I'm at a point now where this is the only thing on my mind all day, every day and it's exhausting. I have to psych myself up just to be myself around my friends and sometimes even my own family just because my self confidence is completely gone, as I seem to spend the whole time just thinking about myself when I should be paying attention to the people in my company, coupled with constantly checking to make sure I'm behaving heterosexually, if you will. As I'm so out of touch with myself I find it hard to truly describe my personality to you, but I wouldn't say I was very masculine, which of course plays on my mind when I'm around people and trying to be a convincing straight guy.

I guess what it boils down to though is what gender I'm attracted to. As I mentioned earlier I do enjoy gay porn, so I guess that rules out me being straight. But straight porn definitely works too. I've always enjoyed the sex I've had with girls, quite a few times I've felt pretty dirty and guilty afterwards but until all this questioning I just assumed it was because they were one night stands and there was no emotional connection.
Looking back on my time with my ex girlfriend I can honestly say that I loved her on an emotional and physical level, I loved having sex with her and always craved it, I loved her company, always wanted to be with her. I adored her. She did make me feel quite insecure but I always put this down to the fact that she was incredibly good looking and coveted, felt like there was a queue of men waiting to jump in as soon as I was out of the picture! And the fact that I was quite an insecure person anyway.
Of course now looking back my brain loves to tell me the insecurity was because I'm gay and was never comfortable in a heterosexual relationship. And I've started questioning all the times I've had any kind of feelings for a girl with something like "is that how it's supposed to feel? Or will I know what true love is when I find the right MAN for me?"

As for my feelings towards men, which I suppose is the conventional way one would conclude that they are gay, I can't say I've ever had any. I can tell straight away when a guy is attractive, but I've never had a strong urge to do anything with an attractive man. Only since all this started have I been looking at attractive men, and wondering whether I'd like to hook up with them. I guess I'd like to try it because it would answer my questions once and for all, but whether I could go through with it is another matter, but deep down I think I probably could. The thought of having sex with any men I know sickens me, but that's probably because they are straight men and it would be weird because they're my friends. Having said that I can think of a load of my female friends I'd like to have sex with, but I still see this as inconclusive as there's only a stigma attached to the former, which is maybe what puts me off the male friends.
I do look at men now and decide whether they're attractive or not, but why did the thought of doing this never cross my mind before I was questioning? Or maybe I was but just not acknowledging it as attraction because being attracted to men wasn't seen as normal? I just don't know. It's really bad, I'm so unconfident around everyone, I look at straight guys talking to each other, having banter etc. and ask myself whether that's how I interact with straight guys. Whenever I'm talking to a girl I'm trying to figure out whether she does anything for me, and when I'm talking to a guy I'm, well... doing pretty much the same, except with them I'm trying to make sure I'm not showing any signs of attraction. It's a real mess.

Right so I failed at not making a long post, apologies for that, but if anyone can be bothered to read it I'd be extremely grateful. I've seen the advice you guys give to people and I've got to say you are one of the most welcoming, honest, kind, caring, selfless and friendly online communities that I've ever come across. Keep up the good work you bloody lovely lot! Might have missed some stuff out but obviously I can answer questions if anyone has any

 

First off, thank you for your answers. Honest answers is what I asked for and that's exactly what I got, so cheers for that.

Amicus, your point about the internalized homophobia is an interesting one. I've read about it before and it seems like one of the biggest obstacles for gay people coming out. Certainly I have no conscious homophobic views, I've always just seen being gay as like being left handed, for example. But I suppose there is this stigma in place, even though homosexuality is always becoming and will continue to be more accepted, and for someone that's identified as heterosexual for 20 years with no reason to doubt that up until the last 6 months, the idea that I might be different to how I thought is quite scary. So yes I suppose I can't deny that is there jamming my signals as you put it, but even when I try to remove the stigma - sometimes I'll think of a scenario where the sexualities are reversed and heterosexuality is stigmatized and I'm there in that world with the feelings I have now - I still can't imagine myself in a relationship with another man, to touch on Lucky's point. But to me that doesn't mean much, I just haven't met many gay men to be honest, so that could just be down to a lack of exposure to potential partners.

Another point that Amicus makes is whether my attraction to women is forced. Again up until the last 6 months I never thought about it because I had no reason to think they were forced. But since all this started I think maybe they have been a bit, but I'm not sure whether my consequential lack of confidence is partly to blame for that; I mean like when you don't love yourself it makes it hard to love someone else. The way I am right now, I find it hard to feel anything towards anyone else because I'm so preoccupied with this lingering issue, which is terrible. So lately if I do hook up with a girl when I'm out, start texting her, maybe meet her for a drink, I don't even know what my true feelings or motives are because I'm so busy trying to figure everything out; I keep having to tell myself I want to do this when instead I should just sit back, be natural and let my instincts do the work.

On that note, let me ask you guys another question. How do you know and how does it make you feel when you're truly attracted to someone? I'm talking more on an instinctive basis, so not so much someone you've got to know and you've come to like their personality, but maybe someone you've only just met. How does it make you want to act around them? Because at the moment I'm struggling to figure out when I'm actually attracted to someone or if I just think I should be attracted to them.