Feel like a failure as a mom

Cheyenne • I an 27 and I have a 3 year old boy, 6 year old boy, a 7 year old little girl, and 16 month old little girl

So I am 2 weeks pp with baby number 3. My other two are 4 and 2.5. I am home by myself with them 48 hours a week when my husband is at work. A full 48 hours. We also have one car so we are stuck at home. I ordered pizza yesterday for dinner because I forgot to put meat out to thaw. Tonight i was gonna make something but the baby needed to eat while I was cooking the meat and it burned. So I just gave up and ordered pizza again. Im just so tired and feel like am awful mom to all my kids.