JakeD,
Sorry to hear about your struggles. Glad you found this place.
My first recommendation is to go to
www.tbiguide.com and read Dr Glen Johnson's TBI Survival Guide. You can read it chapter by chapter or you can download it for print out, too. It downloads to open in MSWord.
With it, you will be able to highlight your symptoms so others can read and understand your symptoms.
If the concussion specialist is truly a concussion specialist, he should be able to explain what you are going through. Unfortunately, many concussion specialists are oriented at determining 'return to work' or 'return to play' conditions and are not much help explaining the symptoms. They are even worse at empathizing with PCS patients. You are not alone. Most of us have experienced this same problem.
There are very few procedures that will image PCS. A neuro-psychological assessment is the most common. Functional MRI can work if done by a skilled technician under a neuro-radiologist's supervision and review.
If you will tell us about your struggles, we will likely have some understanding of what you are going through. We may be able to actually provide some worthwhile help.
I would bet that your biggest problem is becoming overwhelmed. The medical term for this is 'over-attending'. It means the brain is trying to do more than it can currently handle. It can leave you exhausted and in need of sleep and quiet.
You are likely suffering from Multiple Impact Syndrome. It can cause prolonged symptoms and a severe sensitivity to even the mildest movement of the brain. Believe me, I know what this is like. I can get immediate symptoms from shaking my head 'No.'
Please stay in touch. There are many people here for you.
My best to you.