Hm, I wouldn't have told her you loved her.
Thats really good except you should have said all that in person and it would have been hella smooth. Except for the love part you should have left it at like and then asked her out for some tea and crumpets or something. Your an educated young man, and if your smart you can be witty and funny (most intelligent people can, some are just hopelessly dorky) and girls love funny. I was going to say play something on your sax for her, but it's a trumpet. Theres really nothing left, you have to wait for her. You say you haven't gotten notice that she recieved your declaration of love? Do you have classes with her? Do you even see her a good amount? Any mutual friends between the two of you? Social gatherings? Besides the prom thingy. Your going to need to flirt, that pretty much at the point your at. When she flirts back a good amount you know its time to ask her out. You can try and skip the flirting courting stage, but I feel that it's pretty necessary, so you actually know the person before you date them. Then again you've known her for quite a while it seems. So...