I totally freaked out, and we retraced our steps for an hour. I tried not to hyperventilate. At the last bar we checked, the bartender said no one had turned anything in. We looked around our table: no dice. Then we asked the people at the next table over, and a guy (joking, I thought) reached behind his back. And produced my camera!
It was a freaking miracle. I gave him a hug, then bought him a beer. And did a victory dance.
So that was good. Ireland was very good, and I will talk about it soon, I swear. But first: yay for averted disasters.