Wouldn’t have to necessarily be that much depending on when school cutoff was for her. Like I didn’t skip any grades at all and I turned 17 during my senior year just because of when my birthday falls in the year. I was born just before the cutoff and was allowed to start kindergarten at 4. So it really wouldn’t take much as all for someone in a similar boat to what I was to graduate at 16.

To answer your other question, there are a ton of people who think that literally the only reason someone male presenting would talk to a woman is to try to have sex with them.