shitter's remorse
The feeling of remorse you feel after you think you finished taking a shit and you wipe and flush, and you realize you haven't finished.
As I stood up, a wave of shitter's remorse flushed over me as I realized - I hadn't finished.
shitter's remorse
The void of moisture in your body after the act of defecation while already dehydrated. The mental and physical emptiness felt after taking a gigantic shit.
Gordo knew he would soon have "shitter's remorse" as he gazed with dehydration at the over flowing port-a-johns on the third day of the music festival.