Wow! Mine started at 7 months and I thought that was horribly advanced. I'm sure he must be so frustrated in his tiny incapable body if it is housing an intellect like that. Do you have anyone who can share the work with you? It sounds like he is going to need constant attention/interaction for a long time. My son at 7 months was just a live wire and only slept about 5-7 hours a day, never in a clump just bits and pieces of rapid sleeps. It took him years to learn good sleep habits.
Also, get good quality cd's like Bach and Beethoven and the like and let him listen to those. My younger son (started singing at 8.5 months) found classical music very soothing and would listen quietly when I slept. I also found my older son to get hyperstimulated visually, but auditory input was less intense for him.
Then make sure he's getting time on his belly even if he hates it. Those arm and shoulder and upper chest proprioceptors need the input. Apparently kids are more restless these days because of time spent on their back. They don't have a good sense of themselves in space and it overwhelms them. So lots of belly time even if he hates it at first.
and and and well these are just ideas. It's hard to know just what to suggest but those things helped my boys.
