When you pump instead of nurse for a feeding do you get A LOT more milk than when you add an additional pumping session?

I exclusively pump the left but it's an underperformer since I almost let it dry up (total of 1oz per day). I'm going back to work soon 4 month pp I added a 10pm pumping session for my good boob a couple days ago. But I'm only getting half an ounce from that.

I'm getting nervous that I won't be able to pump enough when I go back to work. LO won't take a bottle (yet) so I can't skip a feeding and pump to see how much I get. Is it safe to assume I'll get A LOT more when she's at daycare?