How much blood is too much ?

How much blood is normal after a c section when you start your period ?I'm 5 weeks post c section and I just got my period on the first , now the pain had started subsiding but now I realized I have bad cramps , and my tummy feels hard from above the incision all the way up to my belly button and feels like my skins very bruised to even run my fingers across . Or to try to rub it better . probably from my period . But Im soaking a super pad every 20 minutes the blood is just pouring out and has a lot of very very large clots , I guess my question is how much blood is too much blood ? Or is this totally okay ...