Not making enough milk

Jennifer
I'm no longer making enough milk to save and store. I'm only making enough to feed my son every time he eats. I get 5 Oz from both breasts together and that's if I pump every 3 hours, so every time my son eats. I'll be going back to work soon and I only have 8 bags of breast milk stored up. I don't want to start him on formula, he's only a month old. Any advice?