The compounding of several incidents had driven Greg to this point.
After a late night shower he walked out completely naked, and realized his family was eating dinner and they all gaped at him in shock.
He screamed and ran inside the bathroom to hide.
Another time he went outside and began to piss on the side of the house, but the blinds where open so his family along with his grandparents saw exactly what he was doing.
That night, he dreamed he was Greg Pickle not Patrick Bump her nickel or Jadick Rok Sauce.
The next day at school when they called roll, he screamed "I AM GREG PICKLE! NOT GREG HEFFLEY!"
Then he ran up tripped over a desk fell down and instant ko.
When he woke up his mind was messed up.
When he was at home he thought he was at school, so while his parents were eating dinner he mimed doing homework and knocked over a lot of dishes, and got the stick. "21 gone get the stick!" yelled his dad savagely beating Greg.
At a school assembly he stripped in front of everyone and began rubbing a banana over himself, thinking he was actually at home taking a shower.