So as mysteriously as DD's crazy mood swings and tantums started they stopped. Last night I had a sweet happy baby back. She even ate the food I gave her at dinner (granted it was from my plate, and that seems to help.) The only issue was she refused to go to bed until 10 pm, which is an hour and a half after her usual bed time.
I still don't know what those 3 days of absolute misery were about, but hopefully we're back to normal.
Re: f/u Irritable Baby