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

Other days

blanket fort

Blanket Fort Day
boyfriend

Boyfriend Day
buddy

Buddy Day
coffee

Coffee Day
comfy

Comfy Day
lisp

Lisp Day
brow

Brow Day
bow tie

Bow Tie Day
camera

Camera Day
ask out your crush

Ask Out Your Crush Day