Yes, I was mostly doing just breathing and relaxation exercises and that helped with the shoulder pain plus the neck flexor strengthening with a pressure cuff.
I also stopped almost all computer work.
For stretches I was only doing neck stretches. Basically tilting my head in all possible directions wherever it felt tight (for many hours a day).
Did not do any shoulder exercises because I could not tolerate any.
I think shoulder pain was due to accessory nerve and/or brachial plexus compression. I now have little pain, but some atrophy in the trapezius.

Now that the pain is diminished, I am working on building strength (doing back flys, prone cobras, rubber bands etc). The strength is getting better though there is not much change in the athrophy.
I also do pec and arm stretches now (foam roll, doorframe stretches and the like).