In the flashback, Jimmy throws the Pokeball towards the camera, but when the shot goes to Ballal and his friend, the Pokeball comes and hits Ballal in the head from the opposite direction. When Ballal and his friend go to beat up Jimmy, they run off in the completely different direction of where Jimmy originally was, and yet Jimmy is then seen pinned to a tree, in a completely different place than where he originally was.
During the flashback of what happened at school, JImmy completely loses his lisp. He also is not wearing the wig he wore before, when he decided to be a Pokemon trainer.
Towards the beginning of the first psychiatrist scene, Dr. Phil puts his arm up, as if checking his watch, although you can clearly see, he is not wearing a watch.