As Our Host noted, some feel Sunday is the beginning of the week, others feel it's Monday. The iconoclastic Dreamtime ranks Monday as the end of the week, or at least the end of our week of TRRH "Days of the Week" video countdown.
We wind up our week - which included Ruby Tuesday, Wednesday Week, Old Fashioned Morphine (and Thursday on a Friday), Friday on My Mind, The Heart of Saturday Night, and Sunday Mornin' Comin' Down with Fats Domino's more famous version of Smiley Lewis' Blue Monday.
Blue Monday, written by Dave Bartholomew, was recorded by Lewis in 19 and 54 and covered by Fats two years later, where it became a monster hit for the latter. Lewis always labored under the shadow of Domino, who recorded on the same label, Imperial, as Lewis. Dave Bartholomew once called Lewis the unluckiest man in the world, introducing songs that would later become hits for other artists, but never selling more than 100,000 copies of a single himself.
Sources: Limited Smiley Lewis discography; Tee Nah, Nah - The Story of Smiley Lewis.