Was it because you left when she watched a show she likes? Is she feeling like you are getting your needs met, but she isn't? I don't know. You have to ask her.
Could just be hormones. I'm not kidding, hormones can change us from one moment to the next. I can even feel myself, at some times during the month, saying/doing things that I know I shouldn't be saying/doing. My H calls me on it. It's not necessarily the time of the month you would normally think things would happen either.
