Yes, you can overfeed snakes. Ball pythons have quite a slow metabolism.. eating and digesting takes a big toll on their body, their heart actually increases in size by quite a bit in order to digest a meal.

Just as with humans, being overweight is unhealthy.. plus that, if you feed too often, BPs are much more likely to go on a fast.

Typically you want to feed a young BP once a week.. something that is slightly smaller around than their body is at the widest point. An adult BP doesn't require anything larger than a small rat.