I told last week by my surgeon that i have developed a seroma and i have a weak spot in my abdomen wall . my surgeon gave me an abdominal binder to wear. now my abdomen hurts more. is this common?

Yes: The binding and creation of pressure at the site will also frequently increase pain. You simply may need to get this repaired. See your doctor.

Return to surgeon: If I am interpreting correctly, you have had surgery and have complaints around the area of the incision? Seroma is a fluid collection, not uncommonly seen in the incision, which causes pressure. Assuming it is not infected, the seroma can be watched, or if symptomatic, drained. A binder will only increase the pressure and discomfort. You should return to see your surgeon.