(If this is true) You should tell the police and give them the number where the call came from. When something does happen to you then they know where to start.
this is the most safe way to handle it but at the same time it would make him a joke and fuck up his popularity and repuation :\
I Think you should prepare for war!!
rule #1 just stay calm and don't show others your panic
and #2 first you must call your friends who you trust and ask them to spend the hole day with you tomorrow and in case that person would attack they would interfere so remember to NEVER be alone
#3 carry a sharp knife and as soon as that person attacks you stab him in the hip or the shoulder(personally i suggest the hip) its easier and more effective, and incase you was sent to the court just bitch slapped the police with selef defence especially that you have your own witnesses(your friends)
i'm saying this after an experience, in real life back when i was 15 i stapped a 18 year old senior in the eye with a pencel, when they took me to the police i said self defence and they actually bought it, after i got back to school girls started to think i'm interesting because they thought i'm dangerious and boys started to fear me in someway which made me more comfterable in school.
Now cromiel i'm not encouraging you to choose violince as a way to work things out i mean if there was anyway that would fix things up and keep your dignity and reputation at the same time it would be great, but hey its time for war so i suggest you start preparing for it.