My shoulder hurt as well. I complained and was told it was normal. They told me that my left arm was tied down, straight out, to a board to immobilize it for all the lines, tubes, etc. they needed. Holding it straight out for 5 hours is what did the damage, but it healed.
I was given a really neat water heated pad/wrap in the hospital. It had a water resevoir and flowed warm water through the shoulder wrap. After the first day, a physical therapist was ordered and came to give me exercises to do. She came each day to check up on me and make sure I was doing them correctly. They worked, but it took a few months to be back to normal. I still do the exercises because they help my arthritis.