Hi Port,
I can't really give you much to go on, maybe some of the others will have something better. The one thing I can suggest from my own experience is (and this is going to sound simple, because it is) maybe a thyroid condition??
I have a thyroid imbalance several years ago, and it nearly locked me up, literally. I felt like the tin man, I swear. Like my joints had all rusted, couldn't hardly move. Was in my early 40's, knew I wasn't THAT old.
But my Dr. at the time had overlooked it, preoccupied with cholesterol, liver, hepititus, etc. Missed thyroid, medicine 101, right? A few very cheap pills, and I'm good as new in less than two weeks. I'm still taking those pills, by the way.
That's all I got, and I know it probably isn't your total problem (sounds like you have several), but it is cheap and easy and worth at least asking your Dr. about. Simple blood test, done.
Good luck,
Steve