I finally got an answer, and I've been working on that for a few weeks. I've been having pain off and on, but I really thought it was the knees, and so did the rheumatologist. He said come back in six months, and oh, get an X-ray of your back. He decided it was my knees and my weight. Well, I got the x-ray of my back, but didn't get the results. I asked my chiropractor to look at them, and she shared them with me. Basically I have osteoarthritis of my lower back. The chiropractor has me on a decompression machine which isn't making it worse, and we should see results until next week. The rheumatologist is frustrating but I do sleep better with the gabapentin he prescribed. I'm going to talk to my primary care physician and see what he suggests next. I'm considering going back to physical therapy.