I am tired all the time, short of breath on exertion (ie. climbin...

I am tired all the time, short of breath on exertion (ie. climbing stairs, running, etc.). Have cold feet and hands, especially at night. Also, either feel overheated and too warm or cold and it can change instantly. Have difficulty concentrating, am extremely tired in the morning upon awaking and can hardly get up. I take .05 mg of levoxyl. My TSH tests come back normal, but I haven't felt right since my thyroid surgery for removal of a nodule and 2/3 or thyroid about 3 years ago. I was also diagnosed with sleep apnea shortly after my thyroid surgery. I am not overweight.