One of those

I'm starting out today as one of those days.  That little bit in italics means nothing.  It has been used and reused so many times that nobody is actually sure what it means anymore.  You know it has a negative connotation but aside from that vague bit of knowledge it doesn't tell you anything else.  What are one of those days? 
First of all, you might realize when someone says that, it isn't good.  You will glance over at them to see if you can read their face to gauge the badness factor.  Where does the severity level come in on the badness scale?  Is this a tiny irritation one of those days or a major tension-bundled one of those days?  Depending on how strongly it is said will sometimes give you an indication of whether you should inquire to find out more about it or turn-tail and scoot out of range.  I mean, save yourself.  There might be some fall-out if you stay.  It might be contagious and who wants to inherit one of those days?!
Second, you might inquire and find it isn't really an entire day of badness.  The day might have just started and the person experiencing the badness might be projecting negativity early on and live to prove it throughout the day.  That could turn it into an entire one of those days instead of a brief passing bit of negativity.  Maybe you should inquire about it and flush that idea out of that persons mind before they go and possibly spread contagion throughout the day.  Never a good thing - spreading negative contagion.
Thirdly, you might have to reconsider bringing up the entire idea of starting out early and claiming you are having one of those days.  The best cure is to realize you don't have the illness in the first place.  Even if you start out with one of those days doesn't mean you can't turn it around, right? 
Okay.  I get it.
I started out today as one of those days.  But now I decided it isn't as high on the badness scale as I originally thought.  I won't spread an entire day of negative contagion and I'm only experiencing minor symptions but have no real illness.  It could have been one of those days.
Now it's just a Tuesday.
TT