Constantly sleeping, tired and feels weak when i stand up. on and of fever, 100-104. could i be pregnant? had sex on one of my ovulation day.

Two issues: If you think you may be pregnant get a home test kit and check a first morning voided urine after missing your period. If you are having persistent fevers this should definitely be evaluated professionally. You might start with you family doctor, but write down all your temps, pulse, and full history of any and all symptoms, travel, exposure, etc., and go get examined..