When Sam is shuffling through Dean's cassette tapes, he picks up a Metallica cassette and Dean puts it in, but an AD/DC song plays instead.
In the scene where Dean gets arrested his coat collar jumps up and down.
The sign on the door handle of the motel room gets stuck on the door frame as Dean leaves but is straight a moment later as the cop is walking to the door.
At 16:13 -Blood splatters onto the windows of the car but at 18:24 -The blood is gone.
John leaves Dean a note with the coordinates 35 and 111, presumably meaning 35 degrees north latitude, 111 degrees west longitude. Sam reads a map and says the place is in Colorado. In fact these coordinates are in Arizona, very close to Meteor Crater; the nearest town is Winslow.
Fire Engines in Lawrence, Kansas during the 1980s were painted lime green, not red.
Sam identified Amy's necklace as a "pentagram" when in fact it is a pentacle.
Dean got from the Police Station to Sam's car "in nowhere" in less than 4 minutes. With a gun.
At 34:35- It has been established that "The Woman In White" is cursed and only kills men who have been unfaithful to their wives. Yet she tries to kill Sam.