What do you use for a heat source ?

If you have chosen the wrong source, or the right one but it isn't regulated, it could very well be a burn. Unfortunately, ball pythons aren't the best at judging when temps are too high.

I would say take it to a vet and be safe. A burn can easily get infected and create a lot of problems. To me the $35 for an office visit to find out nothing is wrong, versus $300+ for treating a severely infected burn that will leave permanent scar, I'd go with the reassurance that nothing is wrong.

Gale