Suggest Treatment For Constipation And Severe Shoulder Pain

hi i have not poo,d for 3 to 4 days pain in old op wound lower chest left side where feeding tude was after big big op 14 hours for throat cancer but today and yesterday started getting very bad pain in my shoulders ive taken lactalos twice over two days had a little passing half hour ago is the pain in my shoulders to do with the constipation please tell me it is lol