I am a 54 yr old female. when I was 16 I suffered severe heat exhaustion bordering on heat stroke. There were several years where I had to be careful after that because I would not sweat. Now I sweat too much if in the heat. Ever since that time I have been intolerant to temperatures above 85 degrees F. My face turns red I sweat profusely and and if I keep up what ever I am doing, walking, cleaning whatever my ears will start ringing, I get heart palpitations and feel extremely weak and physically wiped out. It leaves me exhausted. What happened to me? Can it be corrected. I m very frustrated because I want to be out doing things