Not getting much when pumping

Emma • I`m Emma. I`m 23 and happily married to the love of my life. We welcomed a baby boy 5/13/16 by emergency c-section!
I've noticed when I've been pumping that I'll get around 2 oz or more from my left breast, but only .5 (1 if I'm lucky) from my right.  I breastfeed with a shield and supplement ( I pump when he gets a bottle ) any way I can get my right breast to get closer to my left? 
I've also noticed over the last couple days my LO isn't satisfied after feeding from both breasts.  He will pass out but be up 10 min later wanting the boob again and gets mad when he doesn't get much.