She'll be awake all day today and then sleep a lot tomorrow. It's the beginning of a growth spurt. At least that's one of the signs my son has. He'll be up the full 16+ hours I am, then fall asleep and wake up again the next morning and take several long naps during that day and then the next few days he'll be more hungry than normal and by the time the week is over he'll be an inch taller and 2lbs heavier.
Your daughter has already had her 3 week growth spurt (I'm guessing) so you know her signs, but to me that's what it sounds like. Babies have growth spurts at 1 week, 3 weeks, 6 weeks, 3 months, 6 months and 9 months. I'm pretty sure this is her 6 week growth spurt unless she's already had it. As long as she's not fussy or anything I wouldn't worry about it. She'll sleep when she's tired. Hope this helped. Good luck!
at 3:52 AM on Aug. 25, 2009