Oops, it doesn't look like 'hamster and dinosaur day' is a national day..

Other days

promposal

Promposal Day
kiss a ginger

Kiss A Ginger Day
gum

Gum Day
bounce

Bounce Day
youth

Youth Day
cursing

Cursing Day
coffee

Coffee Day
nae nae

Nae Nae Day
bow tie

Bow Tie Day
artists

Artists Day