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

Other days

pumpkin

Pumpkin Day
unicorn

Unicorn Day
me

Me Day
ormille

Ormille Day
one

One Day
pick me

Pick Me Day
my little pony

My Little Pony Day
bow tie

Bow Tie Day
self care

Self Care Day
camera

Camera Day