Like the PPs said, pump every time she gets a bottle of milk to keep your supply up. Keep nursing often because "you need to move milk to make milk."
If you are nursing and then pumping right after, it's normal to get 1-2 ounces after a feeding, so don't worry about that. Just keep feeding her.
If you're worried about your supply, you can try Fenugreek, taking More Milk Plus supplements, or drinking Mother's Milk tea. You can also double check your pump parts to make sure they are still working well (replacing the membranes might help). You can do some breast massage and compression while pumping to get more out of it, or look at pictures or hold her while pumping to see if you can get more that way.