Pain after working out 6 weeks post tummy tuck.

At 6 weeks post op I tried pool walking for a low impact work out. In the pool I felt fine. However after I felt a pulling burning pain to the left lower abdominal area between my incision and belly button. I did call my PS office and his nurse said to rest and give it time. It's been two weeks and I still hasn't subsided. Thoughts ? Also any advice on swelling my is very physically demanding and I work 12 HR shifts. After 8 hours I'm painfully swollen.