Fibromyalgia: I don't have it, but 1 of my doctors says I do. How to change the diagnosis?

However, I DO have a very nasty autoimmune disease, similar, but just this side of worse than systemic lupus. This 1 doctor keeps insisting I try this & that, medication & diet changes, & other hooplah, which do absolutely NOTHING to help my joint pain & oftentimes make it worse. As there are many folks out there who believe they have fibro & can't get a diagnosis, I'm curious to know if there are those like me, who were diagnosed with fibro & know that they do NOT have it. What can a patient do to tell a doctor they are incorrect with their diagnosis without rubbing them them the wrong way? Fibro seems to be a "catch all" diagnosis (at least in the bigger cities of the Northeast) & while I have pain in joints & muscles, I do not have "triggers/trigger points" & found that the antidepressants & Lyrica that were specifically given to me for fibro made me absolutely sick & unsteady; physically & mentally. I am now off of both medications & am feeling much better, but this doctor is insistent & keeps treating me as if all the pain I have is from fibro & not the autoimmune disease working it's "magic" on the affected areas, namely; all the large joints of my body & muscle pain in my mid-lower back & occasionally in my legs. Has anyone else been given a fibromyalgia diagnosis they felt was inappropriate? If so, what did you do to help your doctor change their view?