I'm sorry people like Ian can't be clearer, but he probably does like you very much.
Love Is A Dance
Hearing your story made me think of two young kids who both share feelings, but are too afraid to approach each other -- like at the dance. Actually, since I frequently compare love to dance, it's very apropro. You two are both a bit leery about the dance getting started.
Ask Him Out
My advice is to really take the first step...ask him out. What do you have to lose at this point? You've told him your feelings, you've already confessed the big truths, so now comes the part where you listen to the music and dance. You're a musician, it shouldn't be hard! You've waited and waited, but never made the move, now you can, and you should. Now, as things have gotten started a bit awkwardly, it may continue to be a bit awkward.
Don't Give Up
Don't give up too soon. Guys get all strange when women pursue, but be honest, be the self that he liked so much in class, be the real you, and the awkwardness won't matter! It's hard making the move.
If he declines, or accepts and cancels later, then you know he's either taken, or just not ready for the real and exciting you. But don't get discouraged by this either...the chemistry you felt was real.
You Are Ready
You are getting ready to do the "dating thing" as you called it, and it's clear that other guys are noticing. There will be many more guys if Ian misses this chance with you. Enjoy this awakening!!