I like this girl and I think she likes me back. not sure though.?

Yes she does like you. I'm guessing you're either in middle school or a freshmen in high school...? I was really shy in middle school/ freshmen year, and I liked a shy guy for four year but I gave up because I realized that two shy people won't work unless one person does something. I tried to give him hints just like this girl is giving you hints. But I guess I was always hoping that he would say hi to me, start a conversation with me, or ask me to hang out with him and a group of people. So basically it all lies on you to do the talking if you want something to happen. So man up and go talk to her, maybe you can get a group of people from band (girls and guys) together to go to the movies or something and invite her. Trust me, you'll regret it if you take the initiative and talk to her. Talk to her before somebody else does.