Crabmeat, Just because the MRI says your head and neck are fine does not mean your neck is not injured. The subtle upper neck injuries from a concussion are not able to be diagnosed, especially with imaging. It is usually an instability at C-1 and C-2. BUT, they usually respond to taking proper care of the upper neck. If the headaches include tenderness behind the ears at the bony spot, they are neck related.

Ice the upper neck. Use normal anti-inflammatory meds and treatments.

Treat your neck carefully. Sleep with straight head and neck posture. Limit quick head turns and other movements.