You had bad hair? Always looks fine to me..
Bad hair days != bad hair. Bad hair sounds like bad teeth lol.
How can you have bad hair days without bad hair? :P
It is days when the hair does not do what you want it to do, or does things you don't want it to do (like standing straight up or floating in a cloud around your head instead of hanging silkily down).
I thought maybe it tried to strangle you in the night like a serpent.
No. It is related to having hair longer than 1cm, unlike some.
Ey! Spill the magic potion to us! What is it?