If people are giving out free pain advice in this thread, I have a mystery... I frequently wake up with pain in the left side of my neck, right under the base

If people are giving out free pain advice in this thread, I have a mystery... I frequently wake up with pain in the left side of my neck, right under the base of my skull. When this happens, my right neck flexion is fine but my left neck flexion feels like something is misaligned and stops far sooner than flexing right. I also feel pain at the base of my neck near my SC joint, but a little towards the middle of my clavicle. The weirdest part is that when this happens, i spend all day stretching trying to undo the kink, and what fixes it is something that happens in my elbow - there's a loud clunk and a snap and then my neck feels better, my range of motion returns, and I feel like I have better feeling in my left hand. What gives? It literally feels like a structure(nerve or something) gets misaligned and is getting pulled in weird ways until at one point it snaps back into place.