No, you didn't overshoot by 1. (At least pertaining to UTC-5) the Recent User page is set to a "new day" three hours before the "User Created Quizzes" page is [for us: 21:00 for Recent and 24:00 for User]. Since you submitted a couple seconds apart from us today (which was UTC-4 24:00), the User Created Quizzes page hadn't been reset, even though it said you submitted on the same day. The other 11 were posted after the User Quizzes page update, so you are correct :)