I started pumping the day my baby was born but that’s because he was sent to the NICU and because i wanted to breastfeed they had me start pumping to get the colostrum for him. My milk came in about a day or two after i gave birth
2 weeks after my son was born (i went back to work 4w pp) , a little at the hospital only bc he would latch sloppily sometimes and i was dead tired. don't pump while pregnant, nipple simulation can send you into labor!