Oh-Karen- I feel so bad for you.  I went thru something similar almost 20 years ago.  It was awful and I was beginning to feel that I wasn't sure what I wanted the future to hold.  They tested me for lupus and MS too and I was missing a couple of the "markers" for lupus.  I was just so horribly tired and I was working  (had to-no choice) and would drag my butt to work and then come home and sleep until I had to go in again....and never lost a pound-lol-of course, I didn't!  Anyway, I know what it feels like to live in that anxiety and pain.  For me-it is an inflammatory thing where my body kind of attacks itself.  I am now smart enough to get on an anti-inflammatory when I have a flare. I PRAY that it will be something simple for you too...once they figure it out.  God Bless You and hang in there.  You are loved and supported here!  TRose