I have been taking monodox for three days in order to clear up my dreadful back acne. So far I haven't noticed any kind of improvement, although I'm trying to be patient since I'm still fairly new to monodox, and yesterday I noticed a peculiar red rash where my back acne is. It looks like it's raised, and it burns terribly anytime I try to wash or treat it with my prescription acne foam from my dermatologist. Is this a bad sign?