In the previous story, when Joey poured out his feelings to Rachel, she barely looked pregnant. Suddenly she looks at least 6-8 months pregnant; in fact, she can barely stand on her feet.
When Phoebe is on a date with Jim (James Le Gros), his long hair changes multiple times from tucked behind his ear to hanging over his ear.
When Phoebe and Monica walks into the dry cleaning store they enter it from the street. Whilst inside though, looking back through the glass door, the street has been replaced by a wall with a window.