You have to remember that meat purchased in the store is aged at least a couple days before it hits the shelves.
You just didn't age your birds, so the meat was a bit tough. That's all. No worries.
Just age the next few ones at least a day, some of us age for almost a week, before you cook and eat.
-Kim
Do you 'age' them before or after you butcher/prepare the meat? Like, if I butcher them for breast and legs, can I age those cuts in the fridge before freezing, or was I supposed to age before cutting them up?