If he could get such a thing stuck in his head, Little Wooden Boy would be thinking the phrase "Domo arigato." But the only thing actually stuck in his head was a nail.

Little Wooden Boy would suggest that you have some tea and keep a PDA on you with frequently updated schedule. If you're anal enough, you might be able to at least narrow down the boundries of this missing time. That might lead you to something. Little Wooden might shrug right now if he could.