They're nerve endings are not as developed, true. Their pain receptors exist, however, they are not as complicated as ours. Saying that they do not feel pain at all is incorrect. They are more tolerant to pain and don't feel heat as quickly as it burns. Also keep in mind that the hide was likely where the burn occurred, and the snake probably did not think to leave his secure spot for a bit of discomfort.
Lisa, burns that cover more than 1/3 of the body could mean significant fluid loss and high chances of infection. Even though the burns look like they're healing doesn't mean they are. Healing appears very differently on reptiles than it does on humans and mammals.
That snake could survive with the common over-the-counter creams, but I cannot diagnose that snake through a picture but I can tell that not going to a vet is risking the life of the animal. The vet can make the proper diagnosis and determine if antibiotics are needed, we don't have the credentials to play vet.