I totally sympathise. Our little'un used to see ghosts and auras (when he was 7 and 8) and it used to scare me. Now, I am not a believer in these things but some people do, and friends said maybe he has a wonderful gift - which further freaked me out. But we just have to live with it.
He has imaginary alien enemies, (wish he had some friendly types) so we can't open windows in his room at night even when it is really stuffy.
Every little twinge is pointed out repeatedly because he thinks there is something wrong with him - we all laugh at it to alleviate the frustration, and he knows he is being silly but still does it.
Things have got better, and he moved on to other things - but he still says there are ghosts in the house - who knows, maybe there are.
He hardly sleeps - never did - and both me and mum were exhausted because he needed constant stimulation while he was awake. Now he is a little older (he is 9y 6m) he stays up later anyhow. Still needs little sleep tho'. I feel sorry for you having more than 1!
One thing that did calm him down a bit when he was very young was Omega 3 supplements. They didn't knock him out or anything, but his head just got a little less busy. Don't know if there is any science for this, but that's our experience.
Good luck anyhow and hope this helps - you're not the only one believe me.