The fact that your shoulder pain elevates at night points to the fact that you most probably suffer from a Rotator Cuff problem. The Rotator Cuff is a muscle group that has two functions — to move the shoulder, and to hold the joint in place. If you have been involved in heavy lifting work of a repetitive nature, you need to stop this immediately and consult a physician.
A second problem you might be facing is a problem in the bursa. This is a sack of fluid that acts as a shock absorber for your muscular movements. Swollen, inflamed bursa is a condition that impedes motion of the arm and gets worse at nights.
Bad posture is another cause of these sorts of pains. Sit straight and do not slouch. If your work requires you to sit for extended periods of time, make sure that your chair is ergonomically designed.
Try an ice massage. Tie up cubes of ice inside a thin cloth napkin and rub this on the aching shoulder. Try a soft massage with this too. And a good analgesic gel is a must to see you through those sleepless nights. Physiotherapy and surgery are the final options in case the pain refuses to alleviate. But both these MUST be considered only after consulting a physician.
answered by G R