As far as hurting himself.. I know girls that cut themselves..
I don't think that he's trying to hurt himself but I do think that he is trying to relieve some sort of energy. Not sure what you or his background is but maybe you should try talking to him about it. It doesn't seem that serious except for the fact that he is being a little boy.. I don't mean that in a negative way. But sometimes things are too hard for people to cope with. I would try talking to him and if that doesn't work then maybe taking him to see a doctor or counselor. I had a friend who's friend killed himself and what I heard is that, he was looking for help the entire time.
That may seem really heavy and it's probably not the case but I feel like I should say it given that you are asking for help and any sort of input may help. Being a mother is a beautiful thing. I know you will make the right decision regardless of what happens in the future and what is out of your control.
