You really need to look up Ball Python care sheets. There is a TON of information on how to best take care of these little things. They need an enclosure/tub/cage that has a warm spot, around 90 degrees on the surface, and a cool side, around 80 degrees on the surface. The ambient/air temperature should be in the 80's. Humidity should be between 50 and 60 %. To heat, you NEED a thermostat to regulate your heat source. What are using now for a heat source? These temperatures MUST be very close to these numbers for the well-being of your snake.
If you've only had her for three days, it's likely she isn't ready to eat, especially if her cage conditions aren't ideal. Once you get her temps and humidity all set and steady, give her a few days to settle in. No handling, no feeding, etc.
After that, then try to feed her again, in her tub. I'm guessing she'll be acting like a whole new snake.![]()