Tril, please don't call yourself dumb because that will make me a dummy too. What you did was normal. He was just being an ass, and you were just being nice. Now that you see his scheme, ignore him again. Frankly, what you did is something I'd do too. I would like to see that as being a nice person. Now is the time to stop being nice to him since his friendship wasn't sincere. Please don't drink as a punishment. It should only be done in festivities.
( but for you, really, please don't. :p )