A: It depends on how mature she is! If she is very mature I don't see that much of a problem. Although often these relationships don't work out well you should give it a try hope I could help
A: You should enjoy the time that you have with him. Maybe in a years time your feelings for him or his feelings for you have changed anyway. And who knows maybe you'll board the same university if you love him so much :D
A: I know it sometimes takes some balls but just call her! What could really get worse by doing that? It can only get better :D You might miss out on something if you don't and maybe she might even break up with her boyfriend for you who knows :D Good luck!