Hi Renne
Scar sensitivity is no fun! Here is a post on scar management Scar Management. Can be slow going but works tremendously well. I do not how surgeons and their staff can ethically get away without educating patients on this!
You may also want to check out myofascial triggers in a book called Trigger Point Therapy Workbook by Clair Davies. It is a cheap book on Amazon. There are a number of trigger points in different muscles that refer pain to the back of the head.
Both of these treatments require knowledge, work on your part, time, perseverance, and creativity at times. One attempt resulting in a flare-up does not count as a good try! Be responsible.
It is possible to find a qualified physical therapist who deals with scar management of any sort (Chiarians are not the only ones with this problem!).
Please ask any questions and be sure to post your results!