Question for those TTC that had cesections previously

I am curious if anyone when AF is due amd there is no sign of her ever has their old cesection scar hurt? AF is due tomorrow and I have had no sign of AF yet like I usually do. The only thing is that I have gotten BFN this morning and now my cesection scar hurts and I thought it was odd. I have had increased sense of smell where it makes me sick the last 2 days and I don't think I will get a BFP because my progesterone level was 5.65 at cd21 even though my husband thinks I ovulated late.