My 5 year old is always angry

My 5 year old hits himself when he is angry. He will hit his head with his fist or scratch his arm or face when we try to discipline him. He tells me that no one likes him. When he was in preschool he said none of the other kids liked him and he just started kindergarten and continues to say all the kids and teachers hate him.He says none of the kids will play with him.  Me and his father are seperated and he goes back and forth between us. I noticed that when he comes back from his dads he seems more angry than usual. He refuses to listen to me and when I put him on time out he tells me it's because I don't like him. I explain to him the reason he is on time out and I tell him that I love him all the time but I don't know how to help him at this point. I don't know why he thinks everyone hates him or even where he learned to hurt himself when he is angry. How can I help him?

[sweet_mom20]

im not a doctor but i do do my research and u need find out what makes him mad to the point he will hurt himself and why....did someone teach him that or seen other kids doing that...its normal for a kid to act out but not to hurt themself my best guess is to teach him a different why he can get upset and then when hes done be there to make him feel loved and safe with u as a mom...I would just teach him a different way like when starts doing that just tell no mommy doesnt want u to hurt urself then take him outside and let him throw a ball at a target or let him cry it out its better than hurting himself u need to teach a different way to show hes mad and upset then to hit himself and yeah he can really hurt himself bad if he tryied...take him to talk to someone and change the way he thinks alittle and have them help when hes ready dont push or he will act out more just talk to him and let know ur there.....then go from there hope this helps ya if not talk to doctor or go to webmd and see what they say about this...have a good day and god bless ya