During the opening credits, an old man at the bar orders a large glass of liquor filled with ice. In the next shot, there's no ice in the glass. However, this is a deliberate technique by the director to indicate the passage of time at Trees Lounge.
During the wake, when Tommy and Debbie are praying over Uncle Al (Seymour Cassel) in the casket, he appears to be breathing.
When Tommy reminds Debbie to collect her bag as he is dropping her off, a crew member is visible in the corner of the screen as well as in the window reflection.