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

Other days

self appreciation

Self Appreciation Day
singles

Singles Day
tulip

Tulip Day
lash

Lash Day
girl friend

Girl Friend Day
first love

First Love Day
hannah

Hannah Day
ormille

Ormille Day
ask out your crush

Ask Out Your Crush Day
stud

Stud Day