Venting

Okay I’m a mommy of 6 so breastfeeding not new to me , I currently has a one month old and he LOVE the breast but been a mommy of 6 I rip and run and carpool for school ! So I had decided to go buy him milk for when we are basically out and in the car , BIGGEST MISTAKE !! now I feed more formula then my milk and I do not want that I am lacking in pumping and now I’m just ready to sit and cry cause I wanna breastfeed so today I decided to put the formula up , and just breastfeed on demand !! Can anyone give me tips on how to increase my milk and keep my milk up ?