When Gray and Sam are riding in the cab driven by Gordy, the flag on the meter hasn't been pulled; the fare on the meter visibly stays locked on 2.00.
When Gray is drinking tea, she keeps changing her grip on the yellow mug.
At around 39 mins, when Gray is up all-night pacing, the camera shots alternate between her pacing and a flip clock shown with time-lapse indicating the passing of time. The clock is initially shown starting at around 3:30am, and the alarm time is visible on the face of the clock, set for just before 6:30. However, the time-lapse of the clock pushes through 6:30 and stops at 8:00am, at which point the alarm finally sounds.
The interior scene at Raoul's could not be Raoul's; there is a brass rail behind Gray and her dates, separating them from the bar area. At Raoul's, no such brass rail exists.
Heading for dinner at Raoul's, Gray gets out of Gordy's cab at the intersection of Seventh Avenue and something; regardless of where that something is, it's not the SoHo intersection of Prince and Sullivan Streets. In fact, that far south, Seventh Avenue is actually Varick Street.