Breastfeeding help

Nana10

My baby boy is 10 days old. We had a follow up appointment today and he weighs 5 ounces less than he did at birth, so the doctor is concerned about his weight. He said to feed him 3-4 oz of formula on top of breastfeeding ( 10 min per side) every two hours. This seems like so much because he throws up after each feeding so to feed him more I feel like he will throw up more. Does this seem excessive for a 10 day old?

Also 10 minutes of breastfeeding per side seems so little. He usually nurses for 20-40 minutes on one side and 5 minutes on the side that produces little to no milk. How long are your babies nursing per side and how often? This is my third baby but the first time I’ve had any luck breastfeeding so eventually I would like to only breastfeed once his weight is up.