Do you have a recliner to sleep in? Stomach sleeping is really bad for TOS ..and your back in general , about the worst way to sleep..

It sounds like you are having severe spasms , can you get to any phys therapy for some massage, ultrasound, or something to help resolve the spasms.

Also try not to panic or tense up that clamps down /affects your muscles even more - gentle motions to keep the good fluids going in and bad fluids flow out.

deep belly breathing also called diaphragmatic breathing is beneficial

plenty of fluids/hydrate yourself

try the yoga style corpse pose on your bed or floor and breathe /relax
many times a day..

check our useful sticky threads