My husband and I missed our red-eye flight to Japan yesterday because we mixed up which day we were leaving. In my many years of travel, this has never happened before, and it felt like we were in a nightmare when the gate agent called us at 1AM asking where we were. We were thankfully able to book new flights and rework the beginning of our trip, but $2300 later, we're feeling pretty dumb and demoralized right now.
To make us feel better, what's been your worst flight mistake or mixup?