Catrin, a couple of years ago I was having neck, jaw, and headache pain. I ended up going to a MacKenzie PT, who "cured" me. I did most of the work at home, with exercises she gave me.
I have developed a case of this again, from my stupid accident a couple of weeks ago. I definitely had symptoms of whiplash on the opposite side of my body, so I started doing the exercises again and it is much better. It was bad enough that it interfered a bit when riding, so I had to put a stop to it.
2015 Trek Silque SSL
Specialized Oura
2011 Guru Praemio
Specialized Oura
2017 Specialized Ariel Sport