Milk supply

Xoxo

My baby is 3 weeks old tomorrow and I'm getting between 4 to 5 oz (total from both breast) when I pump. Is this normal? I have the haaka and I dont collect hardly anything when I put it on while hes nursing.. how can I up my supply? He typically eats 3oz every 2 to 3 hours... hes a bigger boy, weighed over 10lbs at birth. Please help!!