Remember that our body temp is much higher than the temp you want for a ball python, and so the hides will indeed feel tepid; or barely warm.
A glass tank can be a tricky thing to get right. Have you tried insulating the sides and back of the tank to help hold in the heat?
Also, a thermostat (as has been suggested) is a must to control the heat sources and keep your snake from getting burned. If you have 2 heat sources you'll need 2 thermostats or a Herpstat II.
Reptile Basics sells a great line of temp guns. These are a great husbandry tool; really a must-have in my book!
Take care. Don't give up. Keep asking questions and being open to corrections and change![]()