Not sure if a girl likes me or not?

I'm going to be a junior in high school this coming school year. She is the same age as me. She ran track this year, which I do as well, but our team is so big I never even knew she existed until the end of the year. I finally noticed her one day when she was running in a meet that I was working (because I suck), and I think she noticed me too. I have never met this girl. The weeks after this up until the end of the season I saw her almost everyday it seems. I was around her a lot, but never had the guts to talk to her. Every time I'd see her she's glance my way, and she has smiled once or twice when she looked at me a few times, but she is usually with her friends jogging around the track or something, so it's not like either one of us can make a move. I've had the opportunity to meet and talk to her several times, but never got up the courage to do it, and I'm kicking myself hard right now. Like one time I was sitting on the ground talking to some guys in the bleachers in front of me, and her and some of her friends walked over and sat within the guys in the bleachers, I kinda glanced at her and she immediately gave me eye contact, then she looked straight down, which I heard was a good sign. Also, I've been doing other things, whether it be at school, or at the track, where I'll be across from her, and facing her, where I'll see her kinda lean over and talk to a friend of hers, and make a slight pointing gesture at what appears to be me. I was trying to think of anyone else she could be pointing to, and I realized I was with different people both times I witnessed her do it, so I figure it was me. Even little things like walking across the track while she lines up for her event, if I look over there, we make eye contact. I really think she is interested, but I cannot be sure, because I've honestly never really had more than a few short dumb relationships out of immaturity. It just seems both of us are always glancing at each other. She is a very outgoing person, as in she is always talking to people (as in friends not talking like about to date), always messing around with her friends, but when we are near each other, she gets real quiet, and almost shy. Do you all think she is interested? Should I pursue it? What are the most common and obvious signs she may be interested? Thanks guy and girls, I really appreciate it.