Honestly, wound reopening is not that common unless there is a clear infection or breakdown happening, and the fact that you have no fever, no pus, and a dry wound are all reassuring signs. That said, some internal muscle soreness and swelling in the lower abdomen in the early weeks after a c-section can just be normal healing, since there are several layers of tissue that were cut through and are knitting back together. Still, I think it is worth going back to your PD or the hospital that delivered you, just to have a doctor physically check the wound and rule out anything internal, because peace of mind alone is worth that trip. It is always better to have it looked at and be told everything is fine than to sit at home worrying.