Great looking boa, but what we need are pic of the enclosure. Also, is his heat pad on a thermostat? Unplug it if not. Ask the person who sold him to you when he last ate, then give his next meal according to age. Humidity is a beast, but impossible to advise without the details of your setup. Also, paper towels are fine for substrate if you have your humidity dialed in. Speaking of dials, wha are you using to measure heat and humidity?
The boa-folk here will get you on the right path, but you have to supply all relevant info.