I suuper recommend a scale, I just have a 20 dollar, a digital food scale! I just put an empty plastic tub on it, tare it to 0 then put Louie in it and track it. Also I feel like ball pythons kind of have little necks and heads haha its what is so endearing to me about them, how their bodies grow so big n chubby but they have tiny cute heads with those trademark cheek bones. Very round and soft creatures. But your snake looks nice n big to me, no loose skin or droopy excess hanging off their bones. Also when they curl up and bend there shouldnt be a ton of excess skin bunched up. That's what makes a snake look healthy or unhealthy to me at a glance but for my own pets I weigh em and keep a chart!!