Has your son been seen by a head injury rehab clinic? There are things they can do or try to help him with head aches and the dark thoughts. There are some new treatments where they target a specific part of the brain to resolve focal head aches if that is what he is having. Has his intracranial pressure been checked? Sometimes, a drain shunt can help with injury induced head aches if they are due to fluid buildup.

At his age, his brain is mature enough to not expect him to grow out of any symptoms.