Does she like me or not?

Ok, firstly, I'm a girl and so is she. Just thought i'd get that out there.

I've been hanging out with her a lot recently and completely fallen for her, and I haven't got a clue if she feels the same way.

She acts kind of nervously around me, we have eye contact but she usually looks away, and i've looked up at her to see her looking at me (could just be coincidental but you never know). We talk non-stop and i make her laugh a lot, but she seems nervous around me. This is kinda what made me think she might like me, just because if she felt uncomfortable around me, there's plenty of other people she could talk to, but she chooses to talk to me a lot.

Her close friend, who is also close mates with me has told me that she thinks I'm great and asks if I'm gonna be there when we all hang out.

I really really like this girl, and don't want to miss out on a chance.

So do I tell her, and if so, how?