I Am A 67yrs Old I Fell Out Side And

I am a 67yrs old i fell out side and fell on my back and my head hit the concrete right onthe back of head really hard this happen on aug 13 on the 26 of aug i went to er my prim. Doctor has no idea why i am having fevers within by body and it does not show when taking tem.she actually thaught i was going through a menopause i went throught that when i was 40 yrs old. Can pain cause the fevers?