should i keep him or let him go?

I think your own intuition is what is making you scared that he will hit you again. And your intuition is probably right. If he makes you feel miserable because by constantly getting angry over little things and you feel intimidated by the possibility of repeated violence, I'd say you should move on. You deserve much better. And he needs anger management therapy.

My personal opinion- take a break from him if it ever happens again. This is a problem he has to solve by himself... but it would be nice to be there if he needs you. And if all that doesn't help, go take a self defense class.
Aken Sol

Yup, split up for the mean time. You know, he will realize how much he loves you and maybe promises not to hit you anymore. Well thats my opinion, Anyway good luck.

Nessa