Help! Breastfeeding problems

Is there anything I can do to keep my milk coming in I'm pumping and still nursing but when I pump I don't get anything really there's time singer and ounce out of each breast or I'll get two ounces out of one and one ounce out of the other or there's times I barely get anything  since last night she's been wanting to eat more every hour it makes me think she's not getting enough to eat. I want to breast feed for as long as I can does anyone know of anything to keep me producing more milk? I really don't want to switch to formula. .