Low fever since june this yr. at 1st had fatigue and sore throat. i feel normal now, temp around 100.1 persists. why? permanent damage possible?

Many reasons: There are many reason why you could have low grade fever. From a normal variant to chronic infections ( sinuses, viral, etc ) or auto immune diseases. You should se a dr to check your white count and CRP and to examine you.

Ur date is advanced.: It's only april and u mentioned fever since june this year. Anyway, ur symptoms could be due to a chronic viral (mononucleosis?), bacterial (endocarditis?) infection etc. See ur dr for a thorough evaluation. Best wishes! http://www.M.Webmd.Com/a-to-z-guides/fevers-causes-symptoms-treatments.