Dont know what to do

I'm currently nearing the end of my freshman year. Today I had a panic attack in the middle of a class and had to go into the hallway alone to work through it. The reason I had a panic attack was because I was in the same room as a guy who has twice previously assaulted me. The first time, during middle school, he was touching me and feeling me up in inappropriate places in the back of a dark classroom and the second time, earlier this year, he was taking inappropriate pictures of me while I wasnt looking. The school didnt do much and my dad doesnt understand what has me so worked up, it was just a bit of touching and some pics, but it's not that stuff that scares me, it's what he hasnt done that he could. It's my horror of coming to school and being scared hes gonna grab me, or my nightmares that he will find out where I live and... I'm trying very hard to deal with it. Once it happened I started wearing baggy clothes and hoods, anything to keep attention off of me, and I frequently had panic attacks. I've had to work on learning to dress again, how to talk again, how to be able to be in the same room as him without flipping out, but it's not enough yet apparently. I thought I was doing well until today when I was overcome with the same panic and terror that used to be there constantly. How am I supposed to get better? How am I supposed to be normal when I'm constantly looking over my shoulder? I know I shouldnt be behaving this way, he didnt even do that much to me, but I do anyways and I dont know what to do to get better...