6 months post c-section

I had twins 6 months ago and I keep thinking something is wrong after the c-section. I bleed for 4 months straight and then started again 2 weeks later. I think I got my period at about 3 months postpartum because the bleeding got way heavier. I asked my OBGYN about it and he suggested an IUD. I had an ultrasound to check things out and everything looked good so they put it in in January. The thing is, I am still spotting and the incision will feel like it’s almost burning and I will get more bleeding. Does anyone have any insight? I bent over the tub to bathe my twins this evening and I got some cramping and more blood. My period isn’t due for another 2 weeks so I don’t think it would be that. I am just tired of it.