Completely confused and don't know what to do anymore

Hi everyone, I'm completely new here and this is the first time I've ever posted on any form of social media website so please bare with me.

As the title says I'm completely confused and just have no idea what to do anymore. I guess I've always known I've looked at girls a lot, but I've always indentified as heterosexual. I've only ever had one serious boyfriend, when I say serious I guess I did like him but I was always finding reasons to put off seeing him and cancelling all the time, we never got further than a kiss and a cuddle so I ended things. I never felt the urge to want to. I've only ever been with one guy which was 2 years we both got super drunk and one thing led to another and it happened, I remember bits and I remember thinking I have no idea what all the fuss is about and quite frankly I couldn't wait for it to be over, I'm now 20 and haven't been with anyone since. I don't feel the urge, I mean I look at some guys and think they are nice and sometimes I think would I wouldn't I? Is there something wrong with me? I've been reading online about a lot of things regarding sexuality, and I'm pretty sure that I have some strong feelings for my friend, she's heterosexual with a boyfriend of 6 years and I can't bare to even be in the same room as them together. I initially thought this might be a phase and it'll go but it hasn't. I find myself looking at girls so much more than I feel I should, I find lesbians super interesting and watch all kinds of YouTube videos and stalk loads on Instagram, is that abit weird? My friends are completely clueless about this and I know I can't talk to them about it. Is this a phase I'm going through am I gay? I have no idea where to start any advice would be gratefully received, thanks very much from Lauren.