In Japan, the first dream of the year (Hatsuyume) is deemed to reveal something about the year to follow. A common greeting in Japan around that time of the year, but especially on January 2nd, is “What was your first dream of the year?” (Donna hatsuyume o mita?)
The first dream of the year;
I kept it a secret,
And smiled to myself.
Shō-u (Tr. R.H. Blyth)
Since people stayed up all night on December 31, the first dream of the year was actually the one occurring on the night of January 1st. That’s why January 2nd is known as Hatsuyume (day of The First Dream of the Year) in Japan.
I hope you had a good dream. Best wishes for the New Year!