I Had Abdominoplasty Two Years Ago And As Of A

I had abdominoplasty two years ago and as of a month ago, the muscles above my belly button area are swollen and distended. I was recently checked out by a doctor who had me do blood work to see if I had celiac & tested me for a few other things and all my tests are normal. He wants to send me to a GI next. I workout at the gym and have been doing abdominal workouts. Could this be the cause for the abdominal swelling? Should I get an abdominal ultrasound ?