Very confused

Before I get to the main topic, there are two things I'd like to say:
1. This is my first post here so hi everyone, nice to meet you!
2. I'm not a fluent English speaker (or writer in that matter) so if there will be some grammar/spelling/punctuation errors (and I'm sure there will) - I am terribly sorry.

So, lately I've been seriously questioning my gender identity. It seems that even though being born and raised as a girl I feel more like a combination of a boy and something quite unspecified. However, what exactly am I (something like trans man but not really?) doesn't really bother me, I don't feel the need to be assigned to any label, I feel (almost) perfectly good with myself and I've been screwing gender roles for quite a long time now (I don't care about the pronouns either).

But there are some buts I'd like to discuss.

First of all: I'm not entirely sure how I feel.
Secondly: I'm really young, about 18. When I was little I have never shown any specific signs of being "boyish", at least I think so. I was willingly wearing dresses, played with rather girly toys (but not really dolls, more like plush animals). I've always hated sports and loved drawing and comic books. The things I've been doing always were girly or "genderless". I was your picture perfect little girl, maybe besides that I've never really liked socializing and any form of having fun with other kids.
When I was about 12, I categorically refused to wear dresses and skirts. Back then I was rather chubby and I honestly thought it was because I was having typical girly complexes connected with pubescence and I didn't like my legs. Now I think I'm fine but something about dresses still feels really... unappealing and if you want to see me in a dress you have to put it on my cold dead body.
Then I started saying things like "I'm not really girly, right?" like I didn't want to be girly. I still say such stuff without thinking about it sometimes. My mum doesn't like it.
For about one and a half year now I've been buying mostly man clothes because I feel really good in them and lately I've been planning to exercise more, to get at least a bit wider shoulders and get skinnier to look more like a boy. I often catch myself on imagining myself looking like a man or people mistaking me as a boy. In last 2 months for the first time in my life I was feeling some kind of dysphoria because of my breasts. To that point that I was thinking about how neat would it be to get breast cancer and get this things cut off without any unnecessary questions from others. However I'm quite fine with my lower parts (well, honestly I wish they would've been non-existing like Barbie's but I don't complain).
For most of my life I believed there were only two genders, I was introduced to all that LGBT stuff when I was like 13-14.
And after describing this situation I have these really clichéd questions everyone asks themselves: is it valid? It's completely new for me and I don't know what to think about it. Is this still real if it occured so suddenly and so lately? Can't this be any kind of hormones swirl caused by my young age? Most queer people know earlier that something is different. Isn't this some hallucination caused by reading too much about queer stuff? Something like when you read some disease symptoms and suddenly you realise you got them all even if it's not true?

There is also another problem. I was wonderig about binding my breasts, but everyone would notice immidiately. It would cause some communication problems when explaining myself, especially to my mother, because how can I explain something I don't understand myself? It was hard enough explaining to her my asexuality.
The thing is that my mother is really tolerant, she would get all that really really seriously. I'm sure she would ask me if I'm feeling like a boy, does she need to call me her son from now on ect. ect. And honestly, I wouldn't know what to answer. No clue. The other thing is she would be super worried and she has just enough troubles (divorce, bad job...). I don't want to complicate her life even more. We don't have the money for doctors, binders, hormones, surgery and all this stuff anyway (and I'm still not sure if I really want this), so maybe I should wait with it untill I'm an independent adult?
Also I don't like to admit it but I'm hella scared that it would break her heart. I've always been her beloved little doughter and now it may turn out it's not a doughter but something queer and werid. She was dissapointed enough when I told her I don't like my name and I'd like to change it in the future. My mother is the only person of whose feelings I care of, so it's the deal for me.
I don't know what should I do. I want to look how I want and do as I feel, but I don't know if it's worth it. It may cause more bad than good.

Thanks for getting though this wall of nonsense. I don't know what can you advise me in this situation, but only knowing that I'm not alone with such silly problems would be really nice.
Thank you.