MRSA is an old and obese disease, @mcshane has a male model body. The chances of him getting it are unlikely. The correct antibiotic for this type of infection that a physician will prescribe him tomorrow when he gets worse is called ‘Sulfamethoxazole and trimethoprim (SMZ-TMP)’ if  that’s not available in whichever area he’s in they may give him augmentin or penicillin and a steroid shot
He can avoid the chills and nausea tonight by simple 2 ibuprofen and clean the wound with alcohol swabs from mckesson then put bacterim on ( don’t cover the wound) drink orange juice, eat fruits, get emergency (vitamin c)  do all that you can preventive care so you don’t have to go to the doctor tomorrow or take antibiotics 

Whatever you do today is your tomorrow