what size habitat does your snake have? what type of heating are you using for it all together? maybe try some ceramic heaters. or some way to cover the openings to lock in more heat. im not going to bash your for not having heat cuz i dont really turn mine on til its super cold yet at the same time your pet is dependant on you for survival right now. so if money is tight, which it often is for lots of people... id find alternative housing during the winter for your snake.
