What do I do in this situation?

ok so I am 14 and I am single. Well I went to the movies with my friend to meet up with this girl i really like. So when she got there we all just kinda hung out. She has a bf but it is long distance. when my friend went to go get a coffee she said she was gonna kiss me for my birthday, so i am like awesome. Well when my friend left to get some coffee she gave me a hug and kissed me like tongue and everything. Well i was happy, we then went into a movie where she said she wanted to be alone with me and my friend sat separate from us. well at the beginning of the movie we were just sitting and i was making her laugh. so she grabs my hand and starts to hold it like a girlfriend would do. and like 5 minutes later she turns to me and kisses me again. I didn't stop her because of course i liked it well when she was done we kept watching the movie. i make a big joker and we both look at each other and she kisses me again! Again i don't do anything and we continue to watch the movie. i pick up her hand and hold it to my chest and turns to me and kisses me again. well the movie ended and we didn't move and my friend comes over and sees us holding hands she doesn't move her hand away so i take it as she is comfortable. well we have went out before but we broke up quick and she is with her bf and i really like her and it seems like she enjoyed herself so what do i do