This girl might like me?

[Jags]

There is a girl in my year at school - S4 (or 10th grade) we are both 15 - , and i really like her. She talks to me most days, and acts pretty friendly overall.

She has had a few boyfriends before, i have had one girlfriend before - that relationship lasted a LONG time though, i.e. A few years or so..

I have not got a CLUE whether or not she is into me, or if she only sees me as a friend.

A couple of weeks ago she started doing things like when we are reading in our English class, she will fiddle with her hair, or tap her fingers on the table. I sit next to her in English, and during this class, I will sit closer to her than other people normally would and she doesn't seem to - i don't think she does any way -react badly. She seems comfortable around me. I have also found out that she wants to be in a relationship - as do i obviously.

Over the last 2 or so weeks, i have been flirting a wee bit with her: i said she has really nice eyes - i said this in person. She posted on twitter something about her being unattractive, i replied with "Since when were you unattractive? " She just denied that she was - as most girls my age seem to do - I found out that she was ill - she has a cold, headache and she feels as if she has been punched in the stomach. I have said to her that i hope she get better soon and best wishes, also said that this gives her an excuse to sit around being lazy though! She responded well to this, thanked me with a smiley face. The following morning i direct messaged her on twitter asking how she was feeling, and if she wanted to rant, i told her i was all ears. She replied to this by saying "nah, not really. Thanks though " I relied to this saying that if being ill was getting her down, or whatever, then she knew where to find me. She replied with "haha, thanks ".
Anyway.. Any help/advice/e.t.c on whether or not she likes me would be deeply appreciated! Also how to get her to like me if she does not, and how/where to take it from here..

Thanks!