Can too much steroids make a rash worse?

I had a rash come back on my butt and was given prednisone to make it go away. I also had left over fluocinonide that my dermatologist gave me before. So i used both of them at the same time. been using both for 3 days now. But today it started to get worse. Like i was fine in the morning then about mid afternoon i put the ointment on and now it hurts. is it because there are too much steroid in one place on my body? Doctor only told me to take the prednisone never said anything about continuing the ointment. I just thought it would speed it up. If i stop the ointment how long until it will go away? Will i feel better over night if my last dose of it was 2:20pm CT?