Just thought I'd mention I've had pains like the ones you're describing, not through PG though. Mine are due to anxsiety & I find it near impossible to breath. If I lay down & put the arm from the painful side over my head & stretch that tends to get rid of it within a minute or 2. Also if I lay on the bed with my head & shoulders off the side stretched out generally helps too.

I know yours may be sue to your PG but thought you may like to try these stretches next time just incase