umbilical granuloma?!?

I took my baby girl to the doctor yesterday because I noticed she had a little ball inside her belly button. Her doctor tells me it's umbilical granuloma and that she's going to put silver nitrate to help it heal. That it's not painful but it stains the baby's skin for a week or so. So today I wake up and noticed her belly button looks worse then it did yesterday!! It looks painful and oozy. Should I be worried???! Is is normal for it to look like this the next day? I'm worried