Recurrent abscess or scar tissue?

Last September I had surgery to drain a perirectal abscess. I healed well but continued to have some mild pain to the scar site. For the past week the area is hard and raised. I thought this may just be the scar tissue as I've been running more and doing squats. I plan to see my surgeon ASAP, but I'm wondering the chances of this being an abscess or if it could just be thick scar tissue. He did say there may have been a small fistula when he opened me up, but I haven't had any drainage since the wound closed.

I always had a temperature too when it was an abscess - this meant infection. I had an abdominal fistula and that scar site sometimes will get hard and then go away - not sure what the deal is, just enough to scare you to think something is wrong.