10 years old but you're new to this so the first questions are how long have you had the snake, what are the temps, conditions, etc, how often were you feeding before.

Ball pythons are lethargic 100% of the time as far as I've experienced so that's not a shocker.

Watery poop or just a constant discharge? I would say if everything else has been stable in the past and changed now suddenly that you could consider keeping a sample of this discharge and have it examined by a vet.