i don't know. i can't examine you but based on the limited information that you shared you need to remain on those antibiotics that i assume your medical provider gave you. a rash on the arm does not imply the infection is in your bloodstream (septicemia). septicemia causes high fever lethargy and you are very very ill.
what happens if the pus from an abscess reaches the bloodstream? . i had an abscess in my right axilla. it was drained surgically because of how painful and big it was. i suddenly developed an unexplained rash in my arm. could this be from the drainage in the abscess?