What do I do??? (20 characters??)?

I feel like my life is slowly breaking apart. I find myslef scared of almost everyone at school and begin to automaticllay think, "is it ok to walk in front of the or should i stop until they p me" this started when a bunch of girls started slapping me as I was walking and I hav now become terriefied of walking down corridors. Everywhere I look, I seem ready for someone to lash out at me or make fun of me. NO, i cannot tell a teacher. my school is big and teachers have already said they cant do much about it. I HAVE ALREADY TOLD THEM . when i get home, i feel like i am slowly going mad as its the only place i am not terrified to glance behind me and i find myslef paniking about what i should do first before i run out of time and have to go back to school. I cry myself to sleep most nights, scared of whats to come in the morning and I always find myself listening to everyones conversations to make sure they arent talking about me and if its sounds like they might, my brain automatically umes they are. Please, is there anything I can do to put my mind in a calm state of mind and not worry for even a few minutes. please? I have been stressed so much i have made myself sick before and I have a feeling i am getting to that stage again. please help ?