Make sure to measure the temperature on the FLOOR of the cage where the snake is and not the temperature half way up the side of the glass on the cage. A lot of people end up cooking their snake because they're not measuring the temperatures where the snake is spending it's time. I personally dislike heat lamps, I think it dries out the air too much. I prefer a heat pad with a thermostat (or a rheostat if you prefer, but you MUST have something to regulate the temperature). Many people are overly concerned about the ambient temperature inside the cage and aren't as concerned as they should be about the temperature of the surface that the snakes belly is resting on which should be no hotter then in the low 90's degree F.

And yes, a humid hide is a good thing to have. Get a shoe box/sweater box (whatever size is appropriate for the size of the snake) cut a hole in the side and fill it full of damp sphagnum moss. Keep the moss moist but not soaking wet.

I've never fed even the smallest newborn hatchling a pinky mouse, they're too small. A large fuzzy or hopper mouse is the smallest food item I've ever fed a ball python. The food should leave a visible lump inside the snake after it's been swallowed.