At two months after a tummy tuck, you are still in the wound healing phase and the swelling may be due to swollen muscle secondary to the repair of the rectus diastasis. A seroma, which is a known complication and quite common, can be diagnosed and easily treated by your plastic surgeon. It would be useful if you would send some pre op pictures as well as data as to your height and weight, both pre and post op, and also the exact surgical procedure your plastic surgeon used. It has been my experience that a well done tummy tuck usually requires a second stage liposuction to get the truly flat stomach most women desire and anticipate from their original tummy tuck. At this juncture, I think it is appropriate to contact your personal plastic surgeon and get his or her views on the subject of your not quite yet flat stomach.