How much are you pumping?

Sarah
I am 1 wk pp and I am breastfeeding at least every 2 hrs. I am trying to store some milk by pumping but I can only manage about an ounce total after a feeding. I've pumped twice a day so far. He prefers one boob over the other so the one oz usually comes from the one breasts and a tiny bit from the other. Is this normal? Should I be getting more milk? How much are  you pumping? I don't want my boobs to be uneven  and I want to make sure my baby is fed a decent amount so if you have any advice let me know :) thank you