Update: The infection on her mouth is back !! 
Woke up this morning and found that the infection is back. Not as bad or far gone as it was the first time. It looks like trying to wean her off of the Steroids did more harm than good. I called the vet the moment I saw any change in her after going from 15 mlg. to 10 mlg but by that time the infection was already taking form. It just wasn't noticeable until I has seen the secretions coming from her nose 10 days into the lower dose.
We are headed back to the vet first thing in the morning for a check up and more than liking another round of several antibiotics. Plus, as hard as it will be on her and for me to see her in such pain, I may go ahead and have the biopsy done if it will help with a positive diagnoses so we know exactly what we are dealing with.
I just wish we could see our regular vet Andrea who is out on maternity leave.