I'm 13 and a older senior girl from school is flirting with me?

I got moved up a grade early so I'm a freshman in high school but I'm 13 years old. I noticed a few weeks after I started that one of the hottest looking most popular senior girls always comes over to talk to me, joke around and hang out at my locker between cles. She nicknamed me her "perfect 10 cutie", she kissed me on the lips 3 times so far, and when she was wearing her cheerleader skirt one time she caught me staring at her thighs but she just smiled and didn't get mad at me. But she always dated college guys before, so I don't know if she really likes me or not because I'm shorter than her, I still don't have hair on my legs yet and I have a young looking babyface, so I look the opposite of those older guys. How can I know if she's flirting with me or just being very friendly? Thank you for any advice.