If time can't erase this feeling...

Well... today was an interesting day. I'm not entirely sure where to begin. Probably should start off with the beginning.
My roommate and I overslept and ended up sleeping through Organic Chem. -_-
Well... anyway... our friends wanted to meet up for lunch at our usual place [yay... seems like things are getting better!!!].
Anyway, all was going well... I got a somewhat usual lunch (usually a cold sandwich with raspberry ice tea). Everyone else was sitting down, and there were no napkins. I put my stuff down and got napkins for everyone. ANYWAY. So I sat down and was eating my sandwich and drinking my ice tea... and my friend, Sagar, looked at me and said "that drink is too cold and you are sick; maybe you shouldn't drink that." The thing is though, I have been drinking raspberry ice tea through my cold; I've been fine. I insisted I was doing completely fine. I ended up basically clawing him (which I do feel extremely bad for). So, lunch is done and I ate my sandwich (or what I could eat) and drank my ice tea. Then, my other friend, Jeff, said to me that he tampered with my ice tea. He was talking about doing stuff to it for a while, but I didn't think he would do anything. However, I, of course, thought wrong. He did. not a lot of tampering... but he still did something to it. So I was angry. Still am. Overreacting? Maybe... but the fact is that he still did that behind my back and knows how I feel about that kind of stuff. Ultimately, this whole thing is a trust issue. It's not the fact of what it was, but the fact that I don't think I can trust him with something insignificant, such as a drink.