My DH has been through cellulitis more times than I can count. It started from a brown recluse spider bite that went into necrotizing fasciiti. He was in the hospital for 2 weeks with IV antibiotics and did a last ditch effort of doubling 2 different antibiotics. The alternative was amputation. It started in his lower leg and spread up to nearly his hip. He had infectious disease doctors called in for this.
Anyway, he’s also been to the hospital for IV antibiotics many times. What was done to him a couple of times, a magic marker was used to draw lines on his leg as to where it was red/swollen. If the infection spread past that line, go back immediately to the ER. Be careful, one time DH was nearly septic from cellulitis. He gets it very bad and it goes south very quickly.
With all that being said, perhaps it isn’t the correct antibiotic for you. If you think it is getting worse, go for the 2nd opinion. It’s your health and you are your own best advocate. If you feel you need to go back to the ER, go. Some ER docs don’t believe DH that he can get so sick, so fast from cellulitis. One time, he had to go to the ER via ambulance and the doctor said his dizziness was from vertigo and his flushed faced was windburn. They did admit him and the doc the next morning was stunned that they couldn‘t see it was cellulitis.
(((HUGS)))