Is this normal ???

Hi. I’m a new mom and my baby is 9 days old. He had low blood sugar when he was born so he needed more then what I could breast feed. We are now doing both breast and formula. He’s doing great eating and I try to pump eat least every 4 hours. ( it’s hard. There’s a lot going on besides having a newborn).

I’ve on Sunday I was able to produce 3.75 oz. twice!

Then suddenly I can only get an ounce at best. 😭. Will my milk increase with more feeding and pumping? I’d rather be giving him breast milk then formula.