I can't leave. I'm a mod...
OK, I get it.. You're young and alarmed about what happened.
Some pointers:
1) You were in a hot sauna and your bladder was relaxed. Very understandable.
2) Lots of women pee when having sex. Look it up. Why should a man be penalized for the same? Another example of the double-standard.
3) You already know that all that apologizing was not helpful... But here is why: Women take all their cues from outside of themselves, like children. She saw that you were freaked out about it, so being a woman, she fed off your energy and freaked out further. In a sense you "gave her permission". It's just like a kid, when he falls down he will look at his parents to see whether he should freak out or brush it off. When you want to examine how women think, just look at children. They are one and the same.
4) This is most important: You need to take the frame back NOW. You need to become unaffected by it. You were in a sauna. The environment caused you to lose control of the bladder. Big deal. You're human, and as I said, MANY women do this. Your attitude toward her should be "Deal with it or go away". No more apologies, no more feeling bad about it. She is trying to shame you (even if subconsciously) and this is not acceptable. She is simply too young and too immature to understand.
5) The puke story is what really threw me for a loop. It's never a good idea to implant movies of even more disgusting things in a woman's mind. Whatever you plant in a woman's mind becomes her reality. She is largely incapable of differentiating fact from fantasy. That's what men do... they are the rational rock that they need in order to maintain some kind of foothold on reality. So YOU need to define reality and what your standards are. Women follow along with that.
When I speak to women, I am always careful to implant nice images into their imaginations. I do it very subtly with the words and phrases I use. I just paint some unicorns and rainbows and let her fall in love with me all on her own. That takes some skilz that come later in life as you gain experience. I'm talking about deep nuance with language here.
So for now, set your standard, that you will not take abuse or ridicule for an accident. You are a young man who is able to define his own reality. This is an opportunity to step up to the plate and get to the next level.
We all have had emarrassing experiences, and this just happens to be yours. I guarantee that somewhere in her life she has peed and probably crapped in her pants by accident. A girl of substance and value wouldn't have reacted the way she did, especially after you apologized.
She is beneath you. She has demonstrated this. Should she still be welcome as a guest in your world? Think about that.