I don't have kids, so don't have the same experience, just wanted to say I think it could be considered a normal reaction. I mean, if you think about the trauma to the area, it's all linked, and AF cramps and the uterus contracting to expel the unnecessary lining, which could irritate the muscles which were cut during your C-section, leading your scar to be painful.

It could even be a little handy having a "barometer" of your body, like old timer's who predict the weather from the rheumatism!

But I'd also be checking it with a GP, 'coz I'm not one of them