I just had this happen with my last litter. They were about 4-5 days early. The pup was crying, crying and wouldn't stop. I took him to the Vet and he had phenomena and sepsis from the umbilical cord. The Vet gave him a shot and shots for all of the pups for a week and he healed up fine.

Listen to his lungs and see if he has any swelling anywhere.

Thanks everyone. It was the heat. They loved the cold ice pack under a towel. The next day it was only 72 F here and pups were very quiet. I was going to try the cold wet towel as I didn't want Mom to eat the ice pack but it's not so hot for now.