When Tina is approaching Robby while brushing teeth, his mouth is full of toothpaste. In the next shot his mouth is clean again.
The sign at the lottery stand shows that the game is on at 13:00. However it is obviously dark outside.
Tino told Tina that he will leave at 2 p.m. However the town clock shows 4:55 p.m. before Tino leaves.
In the driving scene with Nena and Markus you can see that sometimes Markus is moving his lips to his song while in other shots he doesn't.
When in Bed Tina said Robby that he chased away a while rocker gang away. However in the earlier scene it was the superhero gang "The Fantastic Five", Robby wasn't even available when it happened.