Hi tracey and welcome to this forum .....
So sorry you are having to deal with a painful shoulder!
I did not have a frozen shoulder, but following my first surgery three and a half years ago, I developed a very painful shoulder. I finally went to my orthopedist, who said it was bursitis and injected it with cortisone, which helped greatly. At the same time I bought a larger and firmer pillow because what I had been doing was sleeping almost entirely on my non-AN side. That also helped greatly and with some physical therapy it completely resolved.
When my second surgery was scheduled, I was afraid the same thing might happen again so I took great precautions not to sleep with my full weight on my shoulder. This time, it did not happen.
Did your doctor order any physical therapy or offer any other treatments besides injections?
Many thoughts and prayers.
Clarice