One day late

So I'm trying not to freak out, for the past 3 months I've gotten my period (what I thought was early) but was actually spot on in the morning on the day my period was set to start. This month, for the past 2 days I've had mild cramping, but nothing severe and sort of a full feeling, but this morning, when I'm supposed to start my period there was absolutely nothing. Not even cramping or the normal feeling the day of. I know it hasn't even been a full day yet. But this is odd. Should I be concerned, should I buy a test?!