I'd probably be a bit shirty too. If I have to buy something to a budget then I either buy within cents of it, or what is more common is that I do as you did - buy both over budget of what I actually pay, as well as buying well over value because I will buy something on sale.

Sorry you feel a bit peeved, but I'm sure your little one will like it as well as anything else - as my DH constantly tells me, the kids have no idea of monetary value at this point.