Continuity mistake: Prior to the dinner at Fancy's with George's parents they show the restaurant from outside but the person in the window is the Veterinarian that Zoe stands up later this season and it is actually the same exact shot from when he is waiting for her to show up for their date.
Continuity mistake: When Zoe is talking to the nurse about condoms, in the first few shots they are green, purple and orange colored packs and the jar is half full. A few shots later they are only gray and orange and the jar is completely full.