I don't know, difficult situation. This is how a lot of fish play hands like sets or two pair. They slow-play all the way to the river and then suddenly bet big, so he could very easily have you beaten.
i agree. Ignoring over-callers can cost you sometimes, so I would have not bet the river, but it doesn't mean i'd fold the queens...
take your ego out of the equation and judge the situation dispassionately