Symptom that's scarying me. My muscles aren't recovering anymore..?

I only realized this when I tried to exercise again recently. Even 20 minutes on the treadmill leaves my legs sore for over a week unable to build on any sort of cardio program. I have adrenal insufficiency/addison's, my thyroid is low, I'm on testosterone, I have water diabetes. My pituitary system is being completely affected.. and now after my Endo has balanced these hormones out.. My muscles are also being affected.. Unusual cramping. I'm just slowly falling a part and 3 years ago I was in the gym every day with more energy than anyone I knew. I have no exercise ability anymore because my muscles will not recover.

Any diseases that have these symptoms I should try to look into and get tested for?

Specifically, the inability of the body to repair muscle damage? (Although I think they slowly stop aching if I don't use them for a week or two very much.. that goes for just walking around the store and getting around).

Sorry, I forgot to mention. My last treadmill exercise for instance was after a two week lay off and I walked on it for 20 minutes at 3mph. That was over 8 days ago and my ankles are still sore. Walking around to the store or the house exacerbates the problems and I notice slow me down.

I'm 25 years old.

It is strange that you would be lacking the ability to recuperate considering that you are on prescribed testosterone, which is an anabolic steroid. As we know, testosterone is what bodybuilders wish to boost in order to build gargantuan physiques.
It does seem that your biggest problem is that you are getting extreme stiffness/cramping with your workouts, and if this is the case perhaps it is not the rebuilding of the muscles that is the problem. You could have unbalanced levels of minerals in your body, such as calcium/magnesium. These minerals are very active in the ability of the muscles to relax to their normal state.
This is strictly a hypothesis and I cannot say for sure this is your problem, but can be easily tested for by your Doctor.
It would also not hurt to supplement with calcium and magnesium, although you would not want to take them together, as they are antagonistic to one another, meaning that one mineral will block the absorption of the other. Just take them at different meals and see if you get some relief after a week.

Either way it would not be a bad idea to have your Doctor test you for any vitamin/mineral deficiencies as a safeguard.

maybe you should take it easy. you could start at a level you're quite comfortable then after a while, you gradually increase the intensity of your exercise. but if your muscles become hot after exercising, slow it down, you could be giving your muscles too much work. your complications doesn't really have anything to do with your exercising. well, if you are still feeling that your body is still down, consult a doctor regarding your concern. you don't know, it might be something else.