Belly Button Concern

Hi All.  I have a question about my belly button.  I am almost 8 weeks post op and am beginning to notice a little discomfort from my belly button.  It has had a grayish look to the inside 'nub' since the surgery, but not it seems to be getting red around the the outside edges.  I have put an antibiotic on it.  Should I be worried about the gray color inside?  Thanks for any input.