I'd stick one more hide on the cool end and one in the middle of the viv, so he has defferent temp options. If you decide to keep him, order an infrared temp gun or thermometer online ASAP so you know what your temps are, and then get a thermostat if the hot spot is too hot (which I'm guessing it is, just because the heat mats usually are). You aren't a bad owner, you just need to take a deep breath and get back to the basics of what he needs. If you don't know your temps, you can't get them right.
Oh, and I'd offer him food once a week. Three weeks is a bit extreme, especially if he's a young BP (they tend to eat more often than adults).