Have you been around any kids with fifth's disease? In adults the symptoms can be arthritis-like. Some viruses can cause symptoms to linger and cause pain. Rheumatoid arthritis and lupus were 2 things I was tested for when I had symptoms similar to yours, but the tests came back negative. It took about 6 months and lots of Advil, but eventually went away. I take glucosamine /chondroition sulfate /msm and it's not really supposed to work on tendon issues, but I really believe I would have worse problems with the torn rotator cuff if I didn't take it. I also try to stay away from sugar as best I can, because it causes inflammation.Most fruit has anti-inflammatory properties, especially pineapple, and fruit with pits.