Turtlein'
While you are anywhere other than a bathroom, you have to deficate so bad that your fecal matter starts coming out of your ass. In essence your crap is poking out of your ass like a turtle's head.
I had to shit soo bad, I was turtlein' while walking home from school.
Turtlein
Almost shitting your self like how a turtle’s head is peaking out
I was turtlein