1st one, you waited too long to have sex and she couldnt wait anymore. if you talk to her between about 1-2 days without sex she will drop hints she is horny. After i think 3-4 days she does it while you sleep. For 2nd question, during sex, well in my experience at some point she loses control and says she cant take it anymore and what you described happens. Not sure what triggers it but i think its hot. dont think it can be toggled off but try requesting her to stop if she does it