I'm a little confused by what you've said, so please bare with me (i'm a little slow!) It sounds like you know how you feel, but your scared of your mum's response. And thats a horrible position to be in, but i think the question is do you want to be who you are or who your mother wants you to be, and nobody but you can answer than that.
You asked if it makes you a ->-bleeped-<-, and aside from susan's rule that no member can make such a judgement of another, the best advice i can give is that labels are really not particularly meaningful. When i was confused about my gender identity and sexuality, they really did just confuse everything. Whats important is who you are and how you feel about yourself. If that falls into a label then so be it, but i don't think its helpful for it to be the basis of who you are, especially when trying to figure that out.

Hope things work out with your mum, and welcome to susan's! *hugs*