I've had people ask me, "What is it like to have an autistic child ?"
The best comparison I found is a movie.
Every day starts new, there's the opening scene. This sets the tone for the rest of the day.
Next, the plot starts to develop.
As the day continues, the plot thickens.
In Justin's case, just like a movie the day goes from scene to scene. He can be totally happy, than all of a sudden he is crying and upset. He can be in a mischievous mood, and morph into a really good mood. Some days, Justin is in a really bad mood, these days are usually the hardest.
When Justin is in a really bad mood, he does not listen to what he is told to do or not do. He also tends to do things he knows he is not supposed to do. He will do them over and over again.
Sometimes, there are days when scenes jump from one right to another with no warning.
Towards the end on a movie, usually the plot peaks and than slowly lets the viewers down.
This is the same with an autistic child. Whatever the scene has been for the day, by the end of the day it's reached it's peak and morphs into bedtime.