Well, once I break my leg on the growth plate and walked on it for two days out of stubbornness, until I eventually couldn't get out of bed. That was fun, and now I limp whenever I grow. Or the time I had two cysts on my head that hurt to merely brush, so to numb them they stuck needles in. Both sucked pretty bad, but I was little so the memories aren't too bad.
As for traumatic events, most of my childhood I guess would count. I wasn't raised in an abusive household by any means, but the constant fighting between my parents and two siblings left me with a crippling fear of failure and becoming them while growing up. In middle school, I beat up a kid in a fight who was being an ass. Instead of that being the end, his friends spread that he won and constantly mocked me for a year (I had class with them every day), which kinda mindfucked me for a bit. Also, at around 7 I watched a woman have a seizure in a store, then bust her head open after falling. There was a pool of blood around her head, and her husband was freaking out trying to help her. Didn't bother me too much since I've never been squeamish, but it's interesting to see people's reactions when telling the story.
Overall, I've had some shit, but nowhere near as bad as most people I know.