I have unbearable pain in my right upper arm mostly on the outer half away from my body. I had Rotator cuff surgery a year and a half ago and after this started about three months ago I had another shoulder surgery Dec.13. Other than surgery pain I didn't hurt afterward until I started using the arm again. It hurts from my neck through the shoulder  and into the arm. the worst pain by far is in the arm. By night time I am in so much pain I don't want to sit and eat a meal.
hi  post surgery take physiotherapy that will help you out to relief your pain and do neck isometric and strengthening of neck and shoulder strengthening and arm exercises this will be helpful to you wish you good health