I wouldn't say anything to the university unless he continued to Email. My supervisor like I mentioned found his controlling behavior very odd. I did my student teaching at a private school and I feel as if they get away more; for example he often chose to shame kids for behavior. One day he chose to scream at a child calling her a liar in front of the entire class going on to discuss a personal convo between himself and her parents. I never mentioned this to my supervisor but I was disturbed over this event.