Overproducing?

Would I be overproducing? My 2.5 only eats 3oz every 2-3 hours. I can only pump 2-3oz from my left. 6oz from my right. My right will get so engorged I have to pump it all out. My little one has been sleeping more I guess she’s growing through a growth spurt and misses feedings so my boobs get extra full. I’m trying to build a stock for whenever I need to be away from her just in case. how can I fix my left side to produce more? So far I only have 10 bags of 3oz each. I’d love to collect more and just build a small stash