Truly the answer requires an exam. Unfortunately, this is one of the real problems with international surgery. My concern would be that this is a fluid collection. Improperly treated, the liquid you had aspirated can turn in to a persistent problem that could require a fairly extensive surgery to fix. I think it is important that you return to your surgeon, if possible, or try to find another qualified surgeon where you live who would consider treating you. You may, genuinely, have a hard time finding this as fixing another surgeon's postoperative issues can be a lot to ask. If you can return to the DR, that may be your best bet.
On rare occasions you can develope a seroma or fluid collection that persists and need surgeyr to be removed. When fluid builds up and needs to be aspirated it always delays the final results considerably. Be patient and make sure wearing a tight abdominal binder with close follow up from your plastic surgeon.
Swelling of the lower abdomen after in abdominoplasty commonly contributes to unwanted protuberance. This will improve with time.