Is your heat pad on a thermostat? One like so: https://www.amazon.com/Century-Therm...dp/B01I15S6OM/
If not, you should get one asap. A lot of the heat pads can get well over 100 degrees and be too hot! Place the thermostat probe between the heat pad and glass (on the outside).
You also need a temp gun to measure the surface temp of the enclosure from the inside. One like this: https://www.amazon.com/Etekcity-Lase.../dp/B00DMI632G
So you can get an accurate measurement of what you need to set the thermostat at.
By touch is not a good way to make decisions, as snakes are cold blooded and we're 98.6 degrees, so naturally, they're usually going to feel cold to us.