My Snake feels cold to the touch ?

I would think that they retain heat to a degree. They may only hang out on the cool side until they lose a few degrees of body heat, same for the warm side. I doubt they actually go all the way down to seventy something degrees or all the way up to ninety something. That's the whole idea of thermoREGULATION. To stay within a small range, not jump back and forth between extremes. I bet there is an optimum body temperature they're shooting for. That would be the temperature at which their metabolic enzymes work their very best. For humans, it just happens to be 98.6*F. Any higher and the enzymes start to fall apart. Any lower, and there's not enough energy for the reaction to take place, even with the enzyme.

All that said, you still have skin temperature versus core temperature, but because of the way snakes regulate their body temperature, that probably isn't an issue.

I have noticed my snakes feel warm like the heating pad sometimes, but as I said, my hand could just have been a little more cool than usual right before that.