Bad Hair Day?

I had a bad hair day...I went to barber, and the barber freakin cut my hair like she mows a lawn. My hair short like hell, luckily it is the Hols...

That got me to thinking Bad Hair does not last for only a day, it usually last, a least a week or two, sometimes even a month, depending on the growth rate of your hair. Which is to say you will have bad hair until your hair grows back, or you have another haircut.

So, a bad hair is not limited a day? So why bad hair day? Not bad hair week or something?