Oh please don't worry yourself too much, 4 weeks PP still feeling sore around your csection and tummy area is really quite normal! A few of us who had csections took anywhere from 6 weeks to even a few months before we truly felt "back to normal," so that 3-week milestone you're comparing yourself to is honestly not the standard for everyone. What helped a lot from what I've heard is staying on top of pain relief (don't try to tough it out), using an abdominal binder for support, and keeping movement gradual, even walking longer distances can still feel uncomfortable at 4 weeks, and that's okay. One of my mum friends swears the real recovery timeline is more like 3 to 6 months for feeling fully yourself again, not just the 4 to 6 weeks people usually quote. That said, do check in with your gynae or doctor just to be sure everything is healing as it should, better to get a proper look and have peace of mind!