Jimmy Childers was certain of two things: that last night he’d set the alarm to silent (even though it went off this morning) and that yesterday, June 14th, was the perfect day, the likes of which could certainly never be repeated again.

This is the earliest sf story that I’ve seen with a time loop, although there was the earlier 1939 episode of The Shadow.
Jimmy had the queer feeling, which comes over one at times, he was reliving something that had already happened.

Variants

(1)
  1. “Doubled and Redoubled” by Malcolm Jameson, in Unknown, February 1941.
  2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Malcolm Jameson