Breastfeeding.

So my 3 week old since he was born had been consuming a mix of formula & breast milk. I hate using formula but I need to supplement because I can't pump out 2oz every 2 hrs. Not even every 3 or 4 hours unless I breastfeed, then the next 2 feedings, use formula . So just recently as in right now, I just decided I wanted to go full on breastfed only, straight off the boob no bottle . & it was time for his feeding so I got him to latch, my boob was pretty full and was leaking so I put him on, he was taking pretty big gulps, but only fed for 10mins.. then pulled himself off. I tried to put him back on but he wasn't having it kept pushing away. But he was crying so I thought he was still hungry but just frustrated trying to latch,until layed him on my chest and he fell asleep right away. So he should be full right?

After I would bottle feed him, he would finish the bottle but i would have to take it out when he finished & he'll start crying for more. So he must be full cus he woulda been crying...

Is it fine that he only fed for 10 mins..