😰Freaking nervous wreck

So tomorrow I have registration for my senior year of high school. I left it my sophomore year and went to another school for my junior. It works like: this show up when you can its all day. I am freaking out because I am scared to come face to face with my ex who sexually assaulted me. I have already thrown up twice just knowing I have that risk. And it's mandatory for students to go with a parent. Please if you have advice about avoiding an anxiety or panic attack please tell me. I really need it!! 😰😰😰