How did the dunce cap originate?

I've been noticing a rather unflattering side of me lately, where immediately after saying or doing things I shouldn't I catch myself.  I'll be all shocked that I said or did the particular thing, and rather want to take it back.  What happened to humility?  I desparately need it back, and when I pray for it I find it hard to fight through my pride to ask for that help.  It's very frustrating.  I feel like I'm losing my relationship with the world and with the Lord as a result.