Is it his age or could he be mentally ill?

I have dating a man for about 5 months now. Great fun guy for the most part, he is 10 years younger than I am. He seems to get angry and throw little fits. He will knock glasses over spilling things all over and when asked what happened he will say that it was an accident but it's happened several times. He will occasionally not sleep and stay up all night talking to himself angry saying that everyone is playing with him and nobody has done anything to him. He will talk about How bad is ex treated him. Now when something's bothering him he stays up all night talking about me and how stupid my family and I are and how I don't listen to him or respect him. He will go on and on talking to himself criticizing me about everything I do. When he is confronted about his behavior he just smiles and apologizes. This has happened many times now to the point where my neighbors have thought that we were actually fighting and my kids think he is crazy. I care and am truly concerned for him. Is it just his age and immaturity? or is he mentally ill?

Is he on any type of medication or does he do any kind of recreational drugs? I would say mentally ill.

DISCLAIMER: Non-professional with an ideas that could be off base. I'd say not just mentally ill but potentially dangerous. I'm no professional but I have worked with mentally ill people in a mental hospital. This you needs help right away. But be careful. He exhibits paranoid traits and he'll probably get the ideathat you are trying to do him harm. Most paranoidsdon't lash out butsome can decide to fight. Good luck.