With adrenals I feel like there is a type 1 AF, and a type 2 AF. Type one being predominantly cortisol, and type 2 being predominantly aldosterone. Some people have both low, like me :) DHEA is an androgen. It shouldn't be making you bed-ridden. I would suspect low aldosterone.
You've mentioned Orthostasis in the past, please get some 8 am serum aldosterone/renin labs. Also, get your thyroid checked!