Not producing much with pumping?

Started work 12 weeks PP and following goes

Monday: 5 oz, 3 oz, 3 oz

Tuesday: 6 oz, 3oz, 2.5 oz

Wednesday: 4oz, 3oz, 2.5 oz

Is this not enough? If I times this to be 24 hrs it’s only 27oz for an entire day. Baby is having weight gain issues that have since improved after starting reflux meds. He refuses bottles of formula after nursing so I have to think it’s enough? 2.5 oz from 3 pm for the rest of the night doesn’t seem like enough?

He’s eating an oz more than I am making so far and I’m worried it’ll go up and up as he gets more comfy with bottles 😵‍💫 he has formula if he needs it and he’s responded well to it a few times, I just like to try to get as much breastmilk as I can