I have been dx with fibro for around 10 years. I have had knots in my muscles in arm pit and on the inner top part of my right arm. Sometimes they can be very painful, even when just putting on deodorant. I have had a mammogram and doc says it is just muscle knots or lymph node inflammation. I have alot of trigger point pain in lower back that I can not walk far at all sometimes. These have flares in both sites. I have always thought I was hypothyroid but blood test states no. Some of this stuff you have may be fibromyalgia. But the thyroid can cause major problems so stay on top of both. Good Luck to you!
Try trigger point injections. They may help.