Have you gone through a period where you really try to rest (driving, cooking, computer, holding a book, carrying anything, etc.)? If so, has that changed your pain at all?

The things that help me are diaphragmatic breathing (though lying on the floor will initially ramp up my pain but then it usually calms down after 5 or 10 minutes), and ice to the back of my neck (sometimes for several hours, even though that's apparently not how one is supposed to use ice). I haven't had much luck with anything else.

Do you know if, by chance, you have cervical ribs?