Please Help! My ZooMed Terrarium is too cold:(

[MercedesBenz]

Hi everyone,


I bought the 20 Gallon ZooMed Snake Starterkit and this ball python 7 days ago (I have never had a pet before).


The terrarium is too cold! Cold side: 76F, Hot side:82.8F (UTH HeatPad RH-4 mounted underneath the right side).


And I think because of that, my bp is make whistling sound when breathing.

Right now, I am considering getting the ZooMed Repti Heat Cave™ and put it on top of my heat pad.
I don't know if it is too small for my bp though, if it is too small then ReptiCare Rock Heater? [The Q&A says no heat rock but the website says it's ok for snake so I am not sure.]
But I can't think of any other idea to bring up the hot side (Besides mounting an additional heat pad on the side.)
What do you guys think about this? Would it be too hot or "dangerous"?

And I don't know what to do with the cold side in order to bring the temp up

This is my tank:


And this is my bp and it's getting sick because of the temperature I guess