Continuity mistake: When Carrie is showering after being stood up at her party she is not wearing mascara as she stands with her face under the water, then as she opens the curtain to talk to Charlotte again there is no mascara. She puts her hands briefly over her eyes and when she takes them away, mascara is visible all over her eyes and cheeks.
Plot hole: In this episode Carrie runs into Aidan, who now has what looks to be about a 6 month old baby (Tate). This doesn't seem possible, as Carrie and Aidan would have only broken up about a year ago, and Miranda was around 6 months pregnant when they broke up. Brady is only about 5 months old at this point in the series, leaving Aidan only roughly 8 months to have this baby - but Aidan lay in bed for about a month and then dated Nina Katz for awhile. Timeline just doesn't seem to fit.