... warm sensation on my scalp and forehead. I also have a swollen lymph node behind my ear. I took this medicine for possible staph. My roommate had staph and was prescribed bactrim by her doctor. The first dose made her switch, so she got a different antibiotic, so I just took her bactrim. I know I shouldn't have, but I don't have insurance and can't go to the doctor. I stopped taking the antibiotic, but should i be concerned if this goes on another day?