Forshitowing 

When you eat way to much greasy food before bed and you already know you're gonna be shitting your brains out in three hours.

"I'm already Forshitowing my future . It's gonna be a long night after all those wings and beers "

Forshitowing by wonton extraordinare June 14, 2016

foreshitowing 

That feeling you get before you have to take a major shit, letting you know that extreme digestive discomfort is on it's way.

"Man, I'm getting some bad foreshitowing from that chinese buffet. I'm gonna wreck that toilet."

foreshitowing by Denryuu7777 December 9, 2008