Okay, time to put all these silly fears to rest.
Sometimes you just gotta go, whether you're at home, near a public restroom, or four city blocks from the nearest available porcelain throne. And sometimes you decide that you're gonna make it, regardless of the emergency broadcast from your lower bowels, because you don't want to be the type of person who craps on a public street. And because you've never had to deal with an emergency evacuation of such overwhelming certainty.
And just when you thought "losing it" in public was bad enough, you try to act normal as you walk by three young people chatting on a front step. They were talking before you walked up to them, and were dead silent from the moment they saw the back of your pants. But you don't care about them or the various cars passing by on the street, because you're almost safe. Your only concerned about your body not wanting to let you stop what has already begun. And your final concern, upon reaching your destination, is how skillfully you're about to maneuver past your final obstacle: an ascending flight of stairs.
I've quite obviously crapped myself on a city street. Alone, sober, in good health, and in full daylight. And I wasn't upset at all, for some strange reason. But just between you and me, if I didn't laugh about it I probably would have died of shame.