Tantrums at one?

Of course, I just bragged that my one year old was the best ever and today it all changed. She literally threw a tantrum. She was stomping her feet, smacking the couch, sitting down and thrashing her legs, growling, and crying. She was so tired and so frustrated. I had a hard time not laughing, so it was a good thing dad was around to put a stop to it. He put her in time out for 20 seconds and that stopped it fast. She HATES time out. But I wasn't expecting these for another year, or at least 6 months. Hopefully this was a rare thing and it wont happen again for a while.