So, I was at a playground with my two good friends. Then, a really nasty guy from our school came up to us and started to insult and threaten us. He picked up a rock and went up to me, threatening to bash my head open with it if I insult him. He also insulted my dad (that he (my dad) could s*** his d***).
The thing is, he's one or two years younger than me (I'm only 12... ), is shorter and he talks back and shouts at the teachers. Basically, he's like a criminal in making.
What do I do? I'm not a scaredy-cat, I stood up for myself (the reason he actually threatened me, he must hate talk-backs), but he is the type to do rather than spit empty threats.
I already had a bad day and I have some personal issues, which is why I barely had a panic attack. I really need help with this, we go to the same school and see each other in the gates really often, and I see him as a threat to my safety.

(Just saying, I'm from Latvia)

Ask/tell a teacher/parent.