Swelling in the upper abdomen after tummy tuck could be due to several factors. It could be due to a residual pocket filled with fluid called a seroma . If this is the case your plastic surgeon ,after evaluation, may aspirate the fluid. Sometimes it may be due to residual lipodystrophy or fat .In any case you should follow up with your plastic surgeon to determine the reason.
It is not usual that a patient would need to wear Spanx for this long after an abdominoplasty. If there is a problem in this area need to have your plastic surgeon check it out.
If the swelling appears to be isolated there is a possibility of a hematoma or seroma. Generalized swelling is to be expected after in abdominoplasty.
is normal but other issues could be contributing as well. Best to discuss your concerns with your plastic surgeon (since it shouldn't cost you anything) since he/she did your surgery and get his/her opinion if you achieved a good result. Then you can let your surgeon know of your thoughts so further examination of the area can be done to help determine the cause. When muscles are sutured together, the overlying skin is brought along with it and when the opposing sides meet in the midline, you're going to have excess tissue there and that is the most common cause of bulging in my practice.