In the opening scene when Alex stops to pet the kitten while on her bicycle going to work, she has a construction helmet on the back of her bicycle. A few seconds later, as she descends down the hill, the helmet is not there.
After she rescues Jeanie from the strip club, Alex rides her bicycle home in the pouring rain where Nick is waiting. Nick's hair is wet, but Alex' hair appears impossibly dry (outside and inside the apartment).
When Alex and her friend are walking home and they encounter street dancers, there is a police car driving slowly in the background. When another dancer steps in the circle, the police car is farther back and again driving slowly towards them.