Or possibly an earlier one was "Random Quest" by John Wyndham which begins its tale in 1926 In the story he does mention Hitler which makes it more likely as written post war I would think and the story wasn't published in his own name until an anthology in 1961 which makes dating it difficult. However, Wyndham started publishing short stories in 1925 as John Beynon or John Beynon Harris, initially to American science fiction magazines (JW is British), like Wonder Stories.
In this story the protagonist, a physicist, is involved in a laboratory accident and wakes up in a parallel universe - like earth but different, for example India is still part of the colonies. After some confusion and time has past (its unclear how long but certainly months), he accepts the new world (what else can he do) and falls in love with a woman eventually coming to enjoy the life (spoiler alert) before suddenly the laboratory event reverses itself and he wakes up back in his own (original) world, heartbroken because he has lost his one true love. I wont spoil the rest of the love story.
Sounds close to your original and John Wyndham was known for writing short stories with general fiction themes (e.g. coming of age / love / gender related) in a Sci Fi context. As such he was one of the first to include this everyday context - previously the majority of the genre was focused on masculine, boys own, ray guns, epic adventure, comic book type stories (JW did begin with these but rapidly moved on).
Hope this helps