Temp and humidity question?

So right now I'm using 12qt containers for my little guys.
Right now they all seem to be hanging out on the hot side. Now I've read that could mean the temp is to low and they want it hotter. But it reads at low 90s under the substrate with a small layer of aspen. (enough to cover the temp probes) Should I turn up the heat? I don't want to burn them. :/
But I'm also think maybe it's cause on 2 of the cages the back is darker less towards the light (aka scary outside world). But then again on the third cage I have the heat pad on the side facing the light and she still is on the hot side. So maybe I'm wrong.

Do you spray your bps? If so how often? Even when not in shed?

No I don't usually spray unless there is a reason. Usually if the snake stays on the hot side I'd look to the ambient air temps and cool end temps. Typically I like to have 80 cool 90 hot and air 79-85.

Mkay. :3 I'm gonna look into a space heater I think. My room is about 75 so it wouldn't hurt for it to be a little more toasty for all my animals.