Can scar tissue become infected?

About 10 years ago I got my belly button pierced, it was always fine and a "healthy" piercing. When I got pregnant (2 yrs later) I took it out, and soon after my pregnancy what I assume is scar tissue formed. I have had this scar tissue for the last 8 years without incidence (just a small bump about the size of a pencil eraser, no color, no puss, no feeling)... until now. All of the sudden today it is red, swollen and painful, it is now the size of maybe an almond. I am wondering if scar tissue can get infected after 8 years. Thanks for you input. Oh and if I go to a Dr. should I see my regular physician or my dermatologist.... my co-pay is huge and my insurance sucks so I would like to only have to go to one Dr. Thanks!