Actually, this sounds like a growth spurt. Once in a while, baby will hit a period of sudden growth and will nurse more frequently for about 24 to 48 hours.
The time frame for this first growth spurt often coincides with your breasts becoming softer as your body gets used to breastfeeding. Baby also tends to be a little fussier than usual. This confusing combination causes some women to worry that their milk supply is decreasing. Don't stress. Your body — and baby — are acting exactly as they should. You'll need to feed baby frequently for a couple of days as she beefs up, but her feeding pattern should go back to normal soon.