Is it OK to continue swelling each week after 9 weeks post op tummy tuck? Was completely flat week 4 but not now (Photo)

Thank you for the question. Your plastic surgeon will guide you when it comes to specific postoperative instructions.
When a tummy tuck operation is performed, many of the veins and lymphatic channels that normally drain  the abdominal wall are divided (severed).   After the procedure, the abdominal wall swells because these channels are not functioning.  Initially, after the operation, many patients are "pleased with the results"; as swelling increases, the flatness that they appreciated dissipates for a period of time.
  Longer-term swelling after tummy tuck surgery is not uncommon;  swelling may persist for many months and even up to one year after the procedure is performed. Often, patients will report that the swelling increases as their activity level increases and gets worse later on in the day. Sometimes, the use of compressive garments may be helpful to control the edema.  
I ask my patients to where the abdominal wall binder for one month after surgery;  most patients are eager to “burn” the garment  as soon as possible.  Some patients however prefer to keep  some form of compression garment on for a longer period of time, stating that the garment gives them  a feeling of “security”.  The use of compression garments such as "spanx" may be helpful thereafter.
 Generally, it takes many months for swelling to resolve after tummy tuck surgery and it may take up to one year (or greater) a complete skin redraping to occur.
I hope this helps.

It is not uncommon to experience swelling as late as 9 weeks. If you had continued lymphatic massage and compression the swelling would have gone down by now. If not, consider scheduling an appointment again with your board certified plastic surgeon for a re-evaluation and management.