I like him, and I think he likes me. What do I do?

[Heather]

So I've liked this guy since September 2013. He's got a good sense of humour and very friendly to everyone. He tries quite hard to be liked as most people mock him. We share an English class and have been talking to each other for the past few months. We have a lot in common and always have great chats. We go to the same gym, he waves goodbye to me after. He always says hi and smiles. He winked at me the other day at the gym when we were alone. About 3 weeks ago I asked him if he wanted to meet up after his university interview. He said yes and said he would message me. He never did and that Monday he sincerely apologised and we spent an hour together talking. I asked if he wanted to rearrange and he said yes and promised to message me. We still talk in class and he still waves. He hasn't messaged me yet and didn't reply to my Facebook message today even though it said he saw it. He shows all the classic signs that he likes me. Should I tell him I like him? Since it's valentines day?