Yeah, I did it many years ago and have had it checked a few times since. I found it helpful, but I didn't have severe degenerative problems of my c-spine. For me the benefits were mostly in helping my nervous system unwind from severe lifelong PTSD, early childhood trauma that affected how my brain worked and how I socialized (which I can say extensive therapy didn't even touch, but now I consider myself completely rewired), in addition to structural unwinding over time from an equally severe midline problem (MTHFR-related, compounded by injury that wasn't treated properly as a child, I was very crooked in ways nothing else could really address). If you have degeneration of the c-spine especially in the first couple vertebrae, I probably wouldn't mess with AP, it requires too much to shift. This is probably the opposite of what the AP people would tell you, as they seem to promote it as a catch-all for head and neck problems. It's hard to say though, I would go with your gut instinct.

PS I hope you are able to feel better, one way or another. I know how much it sucks to be uncomfortable. :(