Get some digital thermometers like accurite brand sells with probes for the cage to get a quick idea of what temps are and a temp gun to accurately judge them all over the setup. Those sticky ones are straight trash for accuracy and dangerous if your snake gets stuck to them. A thermostat is needed on every heat source to control the output and keep your temperature steady. Cage should be high 77-80 ambient temp all throughout and 88-90 degree hotspot for digestion. That heat lamp and aspen bedding make me think your humidity levels are probably far too low as well.