Oops, it doesn't look like 'nothing nothing day' is a national day..

Other days

slime

Slime Day
african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
chocolate milkshake

Chocolate Milkshake Day
cat girl

Cat Girl Day
self appreciation

Self Appreciation Day
blanket fort

Blanket Fort Day
bounce

Bounce Day
me

Me Day
donate your hair

Donate Your Hair Day
brow

Brow Day