does my exo terra heat pad need a thermostat / rheostat

[edens]

hello! feeling rather discouraged today, i have been getting some info from a fellow member and he mentioned that i needed a thermostat/rheostat....but i cant find the info i need. i talked to my petshop, but i live in quebec and i cant seem to make them understand what i am talking about...lost in translation? they keep telling me my setup is fine, then i am told here that it isnt! honestly i have more trust in you guys!!! so hopefully you can help :-)

i have to move my thermometer and hydrometer, i have to buy some double sided tape first so that it is right above the substrate...right now it is mid tank, which is where the petshop told me to put it....just to show how reliable they are for info!

so basically i have a 100W lamp on top, and a rainforest exo-terra substrate heater which is afixed under the tank on the same side as the lamp. I was told at pet shop, to keep an eye on temps, and if too hot, to raise the lamp a bit (its on a clamp) so far, i have only had to raise it once due to a really hot day. otherwise the temp readings i get seem fine. however i have been told that my snake could get belly burn if not regulated..... so i am at a loss.

when i try looking for the info on the internet...so not helpful all i find are definitions of what they are. i cant find info on how it pertains to Pandora
(a ball python about 15 inches), when i look up python or heating requirements, they talk about heatpads or heat rocks (which shouldn't even be used!) but nothing about thermostat or rheostat...

i myself put my hand on the aquarium bottom (under the substrate) before turning on the light this morning, and it is barley warm, so i think it is okay, but i am the first to admit i am far from an expert. so please help! :-)

thanks so much