Waking to eat/milk supply question!

So baby girl is going to be 3wks old on Thursday, born 11/21. She was born 8lb 3oz and by Monday (4d later) she was 7lb 9oz at the doc appt. I know it’s normal to lose weight after birth. By Saturday morning at her weight check (5d from first appt) she had not gained anything, in fact was 7lb 8oz so lost an oz which I realize could have been a feeding or diaper🤷🏻‍♀️

I was trying to beast feed primarily and only offer an oz of pumped milk or formula when it seemed like she needed it but after that appt I started offering her at least one oz after each feeding immediately because I was nervous that I wasn’t giving her enough. By Tuesday (3/4days after Saturday’s appt) she weighed 7lb 13oz so gained 5oz in that time. Doc was happy with weight gain and told me he felt comfortable with me letting her sleep at night 4.5hrs before waking her instead of the 4hrs I had originally been doing.

This is my second baby and with the first I had the same issue but because she was lip and tongue tied and couldn’t latch to me so my milk supply never went up, this time no ties in her mouth and she latches great-milk supply still not coming up. Maybe I just don’t make any more than this amount???

Anyways, question is. Can I just let her wake up when she’s ready?? She has now been asleep almost 6hrs and I haven’t been waking her to eat the last couple days because I’m so tired, she’s gaining weight not and I figured she would let me know when she’s hungry🤷🏻‍♀️ anyone know more about this? Can I keep letting she sleep?? I just got up to pump because it’s faster than her nursing for 30-45min, then giving formula because she ALWAYS needs more after and then soon after that we are right at the beginning again. If I give her a bottle with the milk all at one time it’s faster and then she is usually good for 2.5-3hrs unless sleeping and then goes longer.

Pic was from 8d old at newborn shoot☺️