make a second impression
To go to the toilet to specifically take a crap. It's another way to say it like "dropping the kids off at the pool". It means doing a number two.
"After eating 3 bean burritos, I really needed to make a second impression."
or
"Don't go in there, I just made a really big second impression."
or
"Don't go in there, I just made a really big second impression."