Hi Barry ,so sorry your having issues with shoulder pain.  I like you had  half of my bowel  appendix and small piece of intestines removed from the right side of my bowel in 2015. I didnt actually have cancer ,but on one of my numerous colonoscopys, after having  benign cancerous polyps  removed from time to time,a flat sessile polyp was found ,which  contained high grade dysplasia. Pre cancerous cells.  So because of a history of loads of cancers in my family I was sheduled to have half my bowel removed,ut wasnt an eady decisionfor me to make,but eventuallyi agreed to operation. 

I am experiencing shoulder pains in both shoulders, had breast cancer in May 2020,so   becsuse of the pain i got ultrasound done on my shoulders,right shoulder I have rotator cuff inflammation and Impingement in it left shoulder I have degenerative arthritis in my neck and left collar bone. I also just had ultrasound recently on my abdomen ,as i was having pains there as well, it showed up that ive developed a fatty  liver ,which also has a small cyst ,these proplems all cause shoulder oain as well . So ask your gp to refer you to get an ultrasound to rule these out ,and voice your concerns that your worried your cancer has returned into your bones.it may not  be bone cancer ,or any thing I've mentioned, you can cause shoulder pain by even turning or trapping nerves in bed or in general day to day activities.  But to put your  mind at rest  please go talk to your gp. I know how hard it Is to get an appointment  as its mostly e consults before they either ring or email you back with an appointment time. 

Good luck ,here from time to time  if yiu want to chat  mostly when I can't sleep lol.