Have you read about the side effects from concerta ?
Concerta can cause you to have seizures ,so I would run and have your son checked for seizures.Make then do a work up on his blood leveles to make sure everything is ok with his levels also. When they check for seizures they should do a EEG and should be done sleep deprived.Best to do as early as it can be done.
Dose your son sleep or want to sleep during the day time ?Is he behind in his age for learning ?
Take a look at these things on line and see if any of them fit your son. There is a lot of information about them on the Web.
Lennox Gastaut Syndrome
take care and god bless.please keep us up to date with how everything is going with your son .