C section infection?

I had my baby two years ago via c section. It got infected once & they put me on antibiotics. Well this morning I woke up and it was a little painful. Almost like fluid under one of the stretch marks I have below my scar. Could this be an ingrown hair or is my incision infected? How can this happen two years later? I plan to call my doctor but wanted to check in here first to see if anyone had experienced this.