Wow, I think this is the funnest thread on Smashboards.
Here's mine:
We were swimming in gym class. At the beginning of class I put my stuff in my locker and went to chat with some friends. When I got back, I saw that my swim suit was stolen. Luckily I had brought two (in case one didn't fit--I hadn't had time to try them on when I bought them), so I put on the other one and went swimming.
At the end of class, we were all changing, and I noticed that a kid who was mentally and physically disabled was wearing my swim suit. I went up to him and asked for it back. He said no. I said it was mine, and he should give it back. He refused. This went on, and got louder, and then I realized that the whole locker room was silent, and everyone was looking at the kid and me.
I'm known to be a nice guy, and I joke around a lot, so nobody told me to quit harassing the disabled kid. They just all looked at me like "What's your problem, you scumbag; stop picking on that kid." They all thought that I was just trying to get the kid to give me his swim suit out of cruelty.
I said that it really was my swim suit, but I don't think anyone believed me. Then the gym teacher came to see what was going on, and just looked at us. I walked away to my locker and got changed.
The kid wore my swim suit every time we went swimming in gym. I guess, if he needed it, it was okay, but I had to buy myself a new one that fit (the one I wore the first day was too small).
Nobody asked if it really was my swim suit; they just assumed it wasn't. I couldn't make them believe it was, but I didn't really try. At that moment I felt like a total jerk, even though I hadn't done anything wrong. I guess it wasn't exactly embarrassing, but it was the worst I ever felt in school, like everyone thought I was some cruel psychotic criminal who likes to torture kittens and mentally disabled kids.