Re: Ball python hide size??
I agree with Luvyna it sounds like that one may be a tad small. I also just wanted to add that different manufacturers size their hides differently, so a medium hide from Pangea would be HUGE for a 3 month old, while the medium from whatever company produces the ones you have may be too small. So don't just buy a large in any brand, make sure you're checking the measurements to see how they compare to the ones you currently have.
It may also be worth making your own hides, that way you can customize them to fix exactly what you need.