What could this hard tender mass after hernia surgery be? (photos)

I had umbilical hernia surgery with mesh on 12/1/15. My abdomen is still severely swollen, and over the past few days I've developed this hard mass above my belly button that extends about 3 inches to the right. It is clearly visible and extremely tender. I'm having a hard time just wearing a tshirt because the slightest touch makes it throb. What could this be? And is it normal for me to be so swollen still? I don't go back for my post op visit until the end of the week.