holiday hangover

Translations
послепраздничное похмелье
After all the celebrations, I suffer from a holiday hangover.
После всех праздников я страдаю от послепраздничного похмелья.
Definitions
A feeling of tiredness, sluggishness, or discomfort experienced after a period of holiday celebrations, often due to overindulgence in food, drink, or festivities, or the abrupt return to normal routines.