Hi jenni,
I wouldn't worry at the moment,if the police haven't picked your boyfriend up yet,he can't have pressed charges, if he does, and this bloke was really worrying you,you were only being defended,I would not think it would be a GBH charge,that is a really serious charge,maybe assault or ABH, I would wait and see if the police turn up before panicking to much, if I can get hold of my mate I will ask him what the penalties are,but at the moment,try to calm down a bit,at least this prat won't bother you anymore,take care, Ray xx