What should i do im now at the point of crying?

Well my ex keeps calling me a rodent and a slag and I'm getting upset and he made my friend upset and I tried sticking up for her and he called me a slag and she has giant teeth and I have been mates with this boy in my class since I was 5 and he was sayign I was a beaver and I have wierd teeth bcoz I'm polish and I fell off my bike when I was 9 what should I do tomorrow I'm gonna go up to him and go how dare u call me a slag and stick up for myself and I'm crying in bed :/