Ben receives a blue string on his right wrist from Kristen earlier in the show to help with his night terrors. Later, while Ben is on his computer looking at articles, the blue string is on his right wrist. After he wakes from his night terror, the blue string is on his left wrist.
When Sheryl holds the dollar bill out toward the candle, the back is seen, upside-down; when the shot is reversed, and the bill is burning, it is right-side up. This happens twice, showing the two different takes being spliced together.