I went thru a similar accident (1998), followed by six months of therapy and a long layoff. Eventually, when I resumed shooting, I needed to drop weight. Then after six months to a year, I notice a little discomfort in the shoulders. Eventually it developed into a sharp pain, when lifting my right arm above the shoulders. It was diagnosed as an impinged rotator cuff (lack of strength and thinning of the rotator cuff). The therapist said, I caught it early, there wasn't any tear, yet.
After five months of therapy and much exercise the rotator cuff was stronger and I resumed shooting. So, I do the exercises every other day, and they have made a big difference.
When I resumed shooting after a 4-5 yrs, I started with 63#, then went to a lighter bow in the winter, and now shoot 54# to 70#. I have noticed a slight temble when holding the lighter bow at full draw (not when shooting). Before the accident, I shot 80 - 90 lbs. In my case it was the opposite shoulder and arm, from the rotator cuff injury. It usually goes away by relaxing, and doing some exercises.
Try pulling the lighter bow, 12", pause 1-3 seconds, then back 18" followed by a pause, then to full draw, pause. Then reverse the process when letting down (18" pause, 12" pause). Repeat 3-5 times from the right side and left side
By increasing my strength on both sides, it has become less of a problem. Conditioning and exercise are important in order to be relaxed while shooting.
I only shoot 1-2 times over a week. Exercising, or shooting should not be done every day. A day rest is important to improve conditioning and strength.