Not pumping enough!

peanut201b

How can I go about increasing how much I'm able to pump? I'm using a manual pump after not having much success with the medela pump in style. I'm getting 6 oz with 5 pumping sessions at 10 min each side. I work full time so with that output I am not able to keep up and have had to start supplementing. I realize that this is a downward spiral but I have to feed her.

She is 9 weeks old.

 Am I doomed?