Based on what you have described-- I'm not sure what other conclusion you could reach except that the child has a very serious mental illness-- either bipolar or schizophrenia. Neither one has an absolute requirement that people experience violence or anger-- this can happen, but its not a requirement for the diagnosis. He needs to be seen by a psychiatrist as soon as possible. Any condition as serious as you are describing will require medication -- and only a medical doctor can prescribe these, a psychologist can't.
Based on what you have described-- I'm not sure what other conclusion you could reach except that the child has a very serious mental illness-- either bipolar or schizophrenia. Neither one has an absolute requirement that people experience violence or anger-- this can happen, but its not a requirement for the diagnosis. He needs to be seen by a psychiatrist as soon as possible. Any condition as serious as you are describing will require medication -- and only a medical doctor can prescribe these, a psychologist can't.
Why do you say it doesn't sound like bipolar? That's exactly what it sounds like to me. I think it would be best to take him to a psychologist and get an evaluation and see what they say. Best wishes.