First of all, was your baby early? My kids were both 3 weeks early and slept literally for like 13 hours straight the first day even though we (me, DH, and several nurses) would undress them, change diapers, tap their heels, wipe them with cool cloths, etc. But then when they'd wake up to eat, they'd nurse for over an hour and each day they'd sleep less and less. (2nd day-7 hours, 3rd day-4 hours, 5th day and on-up every 2-3 hours) So the dr wasn't worried.
Secondly, in the first day or so, you aren't making actual breast milk. You are making colostrum or pre-milk. It's a really thick, dense, nutrient-rich liquid and it's so full of good stuff, your baby doesn't need very much of it to fill their tiny little tummies. Your milk should come in after a few days and then you'll notice that his/her feedings are picking up. And as the previous poster said, you can't go by how much you express as an indication of how much you are actually making. My sis can pump with anything (manual or electric pump) and even expresses by hand on occasion with no difficulty while I can't pump with anything but an electric pump (and that's only if I can pump both sides at the same time. One side at a time and I get nada. Both sides together, I can get up to 6 oz total.) while my s-i-l can't use a pump at all and hand expressing has never worked either.