Well, this was a workout.

[fatbottomedgurl]

I think I would have left the pedal in the shoe and screwed it on the crank as a unit. That way you could use the shoe as your wrench. Ought to get some good torque that way. But why did it unscrew in the first place???

The reason everyone asked which pedal is because the left pedal is reverse threaded- but you knew that.

[snowroo]

Oh you are so smart! Of course using the shoe as the wrench would have been a great idea.

Er, yes, um of course I knew it's reverse threaded {looking sheepish}

[OakLeaf]

I think I would have left the pedal in the shoe and screwed it on the crank as a unit. That way you could use the shoe as your wrench. Ought to get some good torque that way. But why did it unscrew in the first place???

The reason everyone asked which pedal is because the left pedal is reverse threaded- but you knew that.

+1 on that. Crank metal is fairly soft, but not so soft that if the pedal is fully screwed on but not torqued, unclipping would damage the threads.

It shouldn't make any difference which pedal. The left pedal is left-hand threaded because it's a mirror image of the right one. With respect to the direction of travel, the forces on the threads are identical in both pedals. As usual, Sheldon has (had? ) a good explanation.

Do make sure you clean the threads thoroughly (both the pedal spindle and the inside of the crank), make sure they're free of water and solvent, and apply some anti-seize lubricant before you re-install.

Anyway, glad you made it back and that you have a sense of humor about it. Bet you'll carry a pedal wrench now.