Good for you - he flaked on you big time. That's GREAT you said you wouldn't wait - no one should be plan B.
He better get his act together quick. I advise looking for Mr. Right - this guy turned into Mr. Right now.
Seriously - last time a gal said that to me she was trying to date another guy. Just my thoughts. Luckily I wasn't that into her. She did come back, but I said no.