You are still in the healing phase. It takes weeks to months to recovery from tummy tuck surgery. Discuss this with your surgeon as he knows what was repaired at surgery, and should be able to answer your question.
This would need to be discussed as to what elements were repaired at surgery. Fat, skin, and muscle are all part of a full tummy tuck procedure. If a diastasis was not fully repaired, the shape can be compromised. Also, if one is not within 10 lbs of their ideal body weight the intraabdominal contents can dictate the final tummy shape regardless of the repair. Your surgeon can assist you in understanding these elements.
An important part of a full tummy tuck involves tightening the muscles in the mid and upper abdomen. These muscles stretch after having children and can be tightened during a tummy tuck. Your plastic surgeon may not have been able to completely tighten these muscles due to various factors--- such as your pre- procedure weight. Discuss this with your plastic surgeon. He may be able to offer options to flatten out your tummy.