Pain\spasm under right shoulder blade after squats?

Advancing really well on my squats these last few weeks but now I'm developing this new pain.
I only feel it when the bar is taken off my back after squats. It's a pain/spasm right below my
Shoulder blade. Anyone else experience this type of pain? If so.. Any stretches to recommend?
It's really bothersome.. Have to prepare myself for pain each time I put the bar back. Any advice greatly
Appreciated