I ve been having extreme tiredness and shortness of breath going on a year now. I ve had labs, PFT s and most recently a Lexiscan all I m told are normal. I am overweight but that hasn t changed in years. Something I ve done in the past? My dx: are osteoarthritis, asthma, hypothyroidism. I need knee replacements but have to postpone that due to weight (270). I have shocky like symptoms all over my body with no warning, for years. AIC and sugars are good. Been tested for MS twice years ago, both negative. Thank you for your time.