Lost first tail feather?!?

We found a tail feather this morning on the bottom of Tiki's cage and don't know if it moulted out or if it fell out from him being such an acrobat in his cage and then being a clumsy clown having fallen a few times. He'll be 16 weeks on Friday. I read here that the first molt can start around 5 months. Tiki doesn't have any pin feathers yet but we do find at least a few feathers shed everyday (belly feathers only). Actually, I am wrong about pin feathers because my daughter has seen a couple growing from the edge of his cheeks at the border of his beak (near his neck line) but no other pin feathers any where else.

This has me questioning his age again, but his breeder insists she's got his hatch date right of April 10th. He's been quick at "firsts". He was completely weaned by 6 weeks and eating pellets and fruits with no trouble by then. All this doesn't really matter, I am just being paranoid about whether it would lead to health issues that's all.

16 weeks = 4 months. Perferctly normal to molt a little early. Maybe post a picture of the feathers. And maybe schedule an appointment with your vet just to varify that it is indeed looking like a healthy molt and not feather destruction.