Oscar sometimes does this - and my mom's lilac point ALWAYS does this - it's so funny!!!
Perhaps the simplest thing to do is to take a fresh sample of poop to the vet and have them do a check on it. (just turn a fresh clean baggie/ziplock bag inside out, use it like a glove to get the sample, then turn it 'right side out'. )
Hoping your kitty is just a nut like some of the others here.
ETA: I've known some cats to also meow, as if they are announcing their accomplishment!
"You can say any foolish thing to a dog, and the dog will give you a look that says, 'Wow, you're right! I never would've thought of that!'" -- Dave Barry