I had a tummy tuck 2 weeks ago and I realized I have a big lump above my navel and below my breast. What could it be? I caught an infection and was put on IV meds for 3 days. In that time of go to the office every day, we realized a lump. My doctor said he doesn't know what it is (it's not fluids). He did say that he have to go back in and lipo that section. I'm not understanding what's going on. It was flat. What went wrong?