Oops, it doesn't look like 'text back slow day' is a national day..

Other days

self care

Self Care Day
boba

Boba Day
my little pony

My Little Pony Day
lash

Lash Day
frozen yogurt

Frozen Yogurt Day
ponytail

Ponytail Day
nae nae

Nae Nae Day
book

Book Day
bow tie

Bow Tie Day
coffee

Coffee Day