I know you are very nervous and that is okay but please know it will all be okay. It will.
It is very hurtful and beyond stressful (understatement of the year) when people act like total beasts just because they think they can. The important thing is not to react to him (I know you know this!) and do what you have to do for you.
If you have to wear big girl panties be sure they are cute ones!