Paul is handcuffed to a wooden chair in the police station. After the mob chasing Marisa goes through the police station leaving Paul alone, he goes out to the street where he breaks apart the chair leaving the handcuffs still visible on his wrist. He takes an abandoned car to return to Diane's wedding where he gets out of the car and the handcuffs are gone.
Position of bottle that Marisa puts down on the street changes between shots.
The police are not in front of the mob that chases Marisa into the alley, but once in the alley they are leading.
When Gary is stopped at Diane's apartment by the secret service, the agent speaking is wearing a brown blazer. After Gary says, "Who's she got in there?" we cut back to the agent and his blazer is now dark blue.
Eve though they are out of focus, you can see that Paul and Diane are trying to not break out in laughter in the background as they watch Romeo try to hump the cage the first time. Diane (Sandra Bullock) in particular is trying to hide her giggles by covering her mouth.
When Paul steals the yellow sports car after leaving the police station, he takes off and there's a shot of the tachometer over his shoulder. The tach revs up close to red-line, but the engine sound doesn't match.
In the police station, when Paul is handcuffed to his chair, the railings of the camera can be seen on the floor. Policemen walking by are even jumping over them. The railings disappear between shots.
When Paul and his friends are going to Diane's apartment, the railings of the camera are visible on the floor as they walk from their car.
When Diane picks up Paul from the police station. He can speak to her without her falling in love. But she can't speak to him.