Crazy, you were a doctor and aren't sure what the issue is? That saddens me. :(
Have you had a sleep study? They can tell a lot from that.
Have you had your thyroid and adrenals checked out?
I can't stress enough the importance of looking online for a high dose, high nutrient, multi-mineral & multi-vitamin, supplement. Something with many good testimonial reviews for conditions helped.
VERY important for energy and handling stress is Magnesium and the B Complex Vitamins. Magnesium/Calcium/Vit D are especially indicated for muscle and joint pains and problems.
Some of the safer and more effective forms of magnesium include: Taurate, Glycinate and Citrate (latter can be laxitative, so take with food).
Kelp is the richest dietary source of magnesium that I've seen thus far.
FANTASTIC information below:
"Magnesium: The Stress Reliever" by Leo Galland M.D., F.A.C.N. (online article)
"The Importance of Magnesium to Human Nutrition" by Michael Schachter M.D., F.A.C.A.M (online article)
"Magnificent Magnesium" by Priscilla Slagle M.D.