That sounds a long painful time!
Hope things are greatly improved.
I posted about it on the Awning thread but it quickly disappeared off-page, I guess nobody read it.
Briefly for the interest of others, I made an unforgivable howling error: I severely overloaded my small Talon daypack with groceries in Manchester and walked home nearly ten miles with that poorly supported weight pressing down on the shoulders. I did some real damage to the nerves down my left shoulder, tricep and forearm, the pain varied but at its worst was excruciating in the shoulder blade particularly and never subsided enough to sleep properly.
I spent a month on prescription painkillers targeted at nerve pain, but it's much improved now.
...in the end, it was just a waiting game. I visited the physio and they gave me an A4 sheet of exercises and a large rubber band. I don't think it helped me at all, TIME for me was the healer.
Exactly this, exercises might help a bit but injuries of this kind heal in their own sweet time - and that time gets a lot longer as you age!.