How to increase milk supply (or should I?)

My 4 week old baby does ebf, while I (try to) pump twice a day, once after baby sleeps for the night (ard 9pm) and once more after he feeds at night (ard 3am). He usually dream feeds at around 11pm then wake up ard 2.30am, which makes the gap just right (8.30pm feed then pump, 11pm feed, 2.30am then pump). When I pump at night, I do a shortened version of power pump: 15min pump, 10min rest, 5min pump, 5min rest, 5min pump, but would just stop and call it a night if baby wakes up in the middle. He has enough wet and dirty diapers and is gaining weight just enough to keep him on his curve (which is at 10%), so I was under the impression that I was making enough milk. But I realize that I might not be making enough when the other day, I finished pumping at 10pm and basically got woken up at 4am by my other kid and my breasts weren't engorged/hard at all despite the 6 hour gap. How is that possible? They also never do during the day but I thought its because my baby feeds often. I felt them harden only once at day 4/5. So the next day, I tried pumping during the day for 15 mins after 2 hours of not feeding and turns out I only got 60mil (2oz). This is also how much I'd get when I power pump at night. So what should I do to increase my supply before my body regulates? My goal is to be able to pump 120ml (4oz) when I do a pump (2 hrs after a feed) maybe 2 times a day, but not to the point of mastitis, while also preserving my 4 hour stretch sleep at night. And also if I can increase my baby weight percentile (I did this with my twins, from 5% at birth to 45% at 6 mths). Thank you in advance.