I just had a tummy tuck two weeks ago. Is it bad to sneeze? Would it hurt or damage my muscles?

The good news is that most sneezes or coughs shouldn’t be strong enough to do any serious damage to your abdominal muscles as you recover from your tummy tuck. That said, you might notice a tight or uncomfortable feeling during the sneeze, but this should subside fairly quickly. You can try placing a pillow against your abdomen to soften the blow, so to speak, when you feel a sneeze coming on. If you have pain that doesn’t go away shortly after a sneeze or notice any other concern during recovery, don’t hesitate to contact your plastic surgeon’s office.

I would be careful about that this early after tummy tuck.  A good technique is to wear your abdominal binder, and "hug yourself" if you cough, or keep a cough pillow near by and hug it when you sneeze.  It takes some of the pressure off the muscle repair.  You are not likely to do damage, but it will feel better if you do these maneuvers.