You will need a thermostat for the under-tank heater to regulate the temperature. It's a very required piece of equipment. If you don't want to spent big bucks, there is a good $30 one on amazon:
http://www.amazon.com/Hydrofarm-MTPR...mostat+reptile
Heat mats that are always on without a thermostat can vastly fluctuate in temperature, going over 100 F, which will burn the snake. It's only a matter of time without a thermostat. :s
Also, happy ball pythons literally are a rock in their hides all day. Coming out once or twice for a drink of water... If a ball python is very active all the time, it usually means there is something not right with your husbandry, whether it's too high/low temperature or humidity.
ETA: Adding about the pooping... ball pythons can wait up to 4 weeks after pooping before pooping again. These guys are weird.