Oops, it doesn't look like 'shut the fuck up day' is a national day..

Other days

comfy

Comfy Day
frozen yogurt

Frozen Yogurt Day
ormille

Ormille Day
gum

Gum Day
boba

Boba Day
youth

Youth Day
bow tie

Bow Tie Day
first love

First Love Day
carpenters

Carpenters Day
book

Book Day