Diandra, An standard MRI very rarely shows any damage from a concussion. If you lost consciousness, it was a concussion. Looking for a skull fracture at this point is of no value. Same with neck fracture issues.

Most of the non-brain issues are soft tissue strains to the neck with slight displacement of cervical vertebra. An MRI will not show this. Very few radiologist will even look for the very fine signs of such an injury. With DDD complicating the matter, there is no way to suggest what may be new and what is old injury.

The present issue is simple. Treat or deal with the symptoms. Chemo can cause concussion like symptoms as it chemically/toxically challenges the brain (chemo brain).

With your Lyme disease complications, you likely already have learned to deal with prolonged PCS symptoms, other than headaches. Your Lyme disease symptoms are complete overlaps of PCS symptoms.

Do you have any new symptoms ?