It seems there might be a mix-up with the season numbers! While is a highly regarded episode of Supernatural , it is the Season 12 finale (Episode 23), not from Season 1.
: The story introduces a "tear in space-time" leading to an alternate reality —a bleak world where the Winchesters were never born and the war between angels and demons has devastated the planet. All Along the WatchtowerSupernatural : Season 1...
: It finally resolves the pregnancy of Kelly Kline with the birth of Jack , a character who becomes central to the series' remaining seasons. It seems there might be a mix-up with the season numbers