questions about breastfeeding

BoyMom2017

hey, I'm a FTM, and I want to pump. I pump ever 2-3 hrs in the day and every 3-4 hrs in the night. what do I do with b the small amount of milk that's left in the bottle....do I leave it in until the next day or do I poor it into another bottle and sit in the fridge. I'm not producing much as this is day 2 of pumpming. I'm just confused and need some guidance. .. any and all advice welcomed