Continuity mistake: Caroline and Max have just got back to their apartment. As they are talking, the camera switches between both girls. In the background, the shade is originally up. After about 4 shots, the shade is suddenly down, with neither of the girls touching it.
Continuity mistake: When Chestnut is eating his birthday cake, in one shot there are no carrots on top of the birthday cake, then in the next shot there is one still on there. Max then takes the carrot off to feed it to him, leaving no carrots, but in the next shot there is still the one on the cake again.
Continuity mistake: In the open, when Caroline is talking to Max about the cheap tip, she has the money in one hand and the receipt in the other. As Max starts to walk away, the shot changes and now the money and receipt are both instantly in Caroline's left hand.