Did I blow it? How can I fix this?

We're both in high school, and I met her a little over a year ago. She seemed to really like me (at least as a friend, though I suspect a little more than that), she gave me her number, would enthusiastically text me, hug me, etc. I am positive that if I had asked her out at this time, she would have said yes. After a few months, we grew a little distant, she wouldn't text me as much, and I started becoming the one approaching her more times than not. We got in an argument a few weeks before school ended and she was mad at me. I ended up apologizing and she said it was all fine blah blah, but we pretty much stopped talking. A week into summer, she texted me asking me if I was upset at her for being mad at me, I said no, it was a pretty small conversation. This was all before I liked her.

Then school started, and I started crushing on her. Hard. She approached me and said hi, how was your summer, etc. etc. and I started talking to her a bit more, I'd text her a little, but it's just not the same, she doesn't talk to me about her life as much as she used to, she doesn't ask me for advice on her problems anymore, she rarely ever approaches me anymore, I can tell she doesn't care for me like she used to. She clicks "like" on all my "like my status and I'll tell you this" stuff on Facebook, if that means anything lol. In the past week I think I've upset her though, my friend and I played some rude jokes on her (not my idea). I heard from one of our mutuals that she thinks I'm a weirdo. She has a boyfriend now too, but I've never met him.

I think, if she's ever liked me at all, she's moved on and I'm afraid to talk to her too much in case she finds me annoying. Any advice on how I can fix this problem, how to get her to like me the way she did before or what you think is going through her mind?