Boy Trouble

Ok, so I really like this boy but I'm in a really difficult situation. He's a couple years older which is fine (I'm 15 turning 16 in may and he turned 17 not long ago), but I think he likes someone else in our drama group who's playing my best friend in the play. She's really pretty and friendly, and they seem to get on really well.

Me and the boy (don't really want to name him here) are playing characters for our show that are in love and a few days ago we kissed for the first time. It went really quickly and we acted completely normal afterwards. We're really awkward around each other and kind of shy but I do really like him...I'm just worried he doesn't like me back. He seems really flirtatious around this other girl in our group.

What do I do to calm my nerves around him, and what can I do to perhaps make him like me back... (if that makes sense and isn't too cliché) I really need help here.

Thanks!
Ellie