I have a sharp pain in my left side just below my breast when breathing should I go see my doctor?

Yes. Any pain on the left side should be evaluated although it sounds like you may have pleurisy. This is a benign condition that can be a result of a virus. If that is the case usually an NSAID and some heat will help and it will resolve on its own. If it doesnt get better quickly or gets any worse, see your doctor.