Oops, it doesn't look like 'acorn dick day' is a national day..

Other days

comfy

Comfy Day
slime

Slime Day
cat girl

Cat Girl Day
self care

Self Care Day
buddy

Buddy Day
boba

Boba Day
boy friend

Boy Friend Day
self appreciation

Self Appreciation Day
promposal

Promposal Day
prosecco

Prosecco Day