Lots of post concussion syndrome symptoms can be psychological rather than physical. Any bone injury would be long since healed, and any hematoma would be absorbed by now. You'd be dead if you had been bleeding into your skull for 3 years.

If it is psychological, a therapist may help you overcome these symptoms. Maybe if you print out what you wrote and show it to him/her.

I've personally had a lot of physical symptoms that I'm now seeing may be psycological, and therapy does help.