What Causes Peeling Of The Lip Skin?

Hi, about a week ago my doctor prescribed a tube of Mupirocin & told me to put it on my lips because i think i got some kind of bacteria or what not on it, and my lips were breaking up/ swelling/ and feeling kinda wet from whatever was coming out of it. I did as he told me to , but i don't know how it's supposed to make my lips better. The Mupirocin on my lips turn hard after a while, leaving my lips white/yellow-ish. But when i get it wet, my lips become soggyish, and the skin that was growing back peels off. It was supposed to be better in 5 days, but it's been a week now. What should I do?