Stabbing/Stinging/Burning pains inside my abdomen 4 weeks post tummy tuck - wondering why?

It's hard to determine what exactly is going on without a physical examination. Sounds like you have some nerve irritation either from your surgery and or your subsequent seroma treatment. Close follow-up with your plastic surgeon is going to be the best recommendation that can be made

The recovery from abdominoplasty can be difficult for at
least a number of weeks. As the sensation improves and as the swelling goes
down, there can be stabbing, stinging pains that occur occasionally, but almost
always by three months completely resolved. Many patients also experience some
muscle spasms which can be sharp, stabbing pains. They resolve as well.
Sometimes muscle relaxants can be helpful. Rest assured that these areas of
discomfort will subside as the swelling and healing continues. Hope this helps!

Sharp stabbing and shooting pains after surgery is a sign of the nerves that were stretched or pulled are starting to heal and "wake up". This will subside in time and typically gets less intense and less frequent quickly.Massaging the tissue stimulates these nerves to feel the pressure sensation of the massage and not of the inflamed healing segment of the nerve. Ask your plastic surgeon if he/she has any recommendations as well.