That Really Just Happened

I was just sitting on my bed wasting time with online riddles when I should be filling out a job application.  I'd like to emphasize that I was not eating anything.  And then my tooth just randomly got chipped.  I just happened to rub my tongue against it and a piece fell off of the top.  It's about one-third of the width of the tooth gone right out of the middle of the top.  It's not a whole lot, but that is so bizarre.  And now my tongue is going to be all raw since I can't stop running it over that spot.  It's not like my tooth was rotten or anything disgusting like that.  I brush my teeth at least twice a day and I've never had a cavity.  I just don't understand how this would happen.