A crippling panic which arises after taking a shit when you suddenly realize someone is waiting to use the
toilet immediately after you and (a) you left a shit stain in the
toilet that can't be removed and/or (b) you left a catastrophic stench that would
choke a horse.
Person 1: Dude, I almost died at Sherry's
house. I took a nasty shit which left a skid mark on the
toilet, it wouldn't come off, and her hot
sister was waiting for me to use it.
Person 2: Whoa, dude. That's a classic case of Post Traumatic Shit Disorder (PTSD)