I realize it's a bit late but to keep a snake warm in an emergency you can secure it in a bag and then put the bag down your shirt.
Overnight put the bag into a small tub and put the tub under your bed covers with you. The tub is to ensure that you don't roll on the snake in your sleep and crush it, and to keep any snake pee/poop from soaking into your bed if your snake makes a mess.