I've been doing a little research. But first a little back story...

I've had problems with my right shoulder for about 6 years. I have pain that can be intense, but that comes and goes. Like, it will hurt for a couple weeks to a month, then it will go away, sometimes for months at a time. I actually went off of work for it in July, and spent a lot of time with an orthopedic surgeon and in physical therapy. I had x-rays done of my neck and shoulder, MRI's of both my neck and shoulder, and a nerve conduction study of my shoulder. Everything came back normal. There's no swelling, no bruising, no injury. I've had plenty of sprains and stuff before, and usually some ibuprofen is enough to at least take the edge off the pain, but my shoulder is another monster all together. Powerful narcotics may take the edge off, but they don't get rid of the pain. I've been prescribed Narco, Vicodin, and Tramadol for it, and none of them get rid of the pain. I mean, the pain can get so bad, like last night, where even taking a seroquel, I can't sleep because every time I move, it's agony.

So anyway, I've been reading into Somatoform disorders, since the next step seems to be that it's just in my head. Well, Pain Disorder seems to fit. However, one of the criteria for it is that no other psychiatric conditions are present. Well, as long as there is no mood or anxiety disorder present, anyway, because they say that those can account for unexplained pain. I've not heard of mood disorders causing physical pain like this, has anyone else? Or does anyone else have any other ideas? I'm getting really tired of being in pain when no doctor seems to even be able to tell me why. I just want an answer.