The one thing I can think of to suggest that helped me a lot for both my neck problems, and my headaches with my PCS was Physical Therapy.

Yes, I know that sounds crazy, but even though I'm now done with the therapy in the hospital setting I went too, I have what is called a Tens machine that I use at home, it takes care of the tension and headaches that happen at home.

The other thing that helped emensely when we thought nothing was going to,
my therapist and I. Was to stretch my neck. With traction, it felt really good, and it relieved the headaches too.

Donna