Not feeling right 6 days postpartum

I’m 6 days postpartum and haven’t been feeling right. I’m super tired, feels like my head is super heavy. I’m starting to feel nauseous and get diarrhea. I don’t have much bleeding anymore at all. I get really sweaty, then I get cold from the slightest change in temperature. I get this mostly at night. I’m also breastfeeding and have a very demanding toddler. Is all this normal? Is it just postnatal fatigue?