Mama, I know it's worrying when baby's poop pattern changes like that, please have her checked by your pediatrician right away, especially since it's been 3 days na. Better safe than sorry with babies at that age. While some babies do have mild tummy changes after vaccines, a doctor needs to see her to make sure she's staying hydrated and that it's nothing else. One of my mum friends' baby also had similar after her shots, but her pedia checked immediately to rule out other things, peace of mind lang talaga, and baby got better. Don't wait pa-iba if she seems feverish or lethargic, okay? Let us know how she's doing!