Help please!!

Ashleigh • FTM to a beautiful baby girl born January 17th
Okay so I have no clue what I'm doing. I'm trying to also pump because I want to build up a supply for when I go back to work but I don't know if I'm doing it right. I'm getting like 2 some times 3 oz total. I have no clue what I'm doing wrong. Baby girl seems satisfied after feeding. She latched for about 10 mins on each breast at every feeding. She takes about an once after of formula. We are supplementing. I try and pump after every feeding. 
Any advice is appreciated