Sleeping for 8/9 hours straight

Hello moms, my 7 week old LO has been sleeping through the night pretty much right after she's been born. We started out waking her every three hours to feed but found out by accident on night 3 that she could already sleep through the night (something went wrong with the alarm). Because she was gaining weight so well and fast we were told to stop waking her to feed and just feed her on demand.

Ever since its been maybe 3 times that she's woken up in the middle of the night (4 am). Otherwise she goes to bed when we do (11 pm) and wakes up around 7 or 8 am.

It had me worried because babies that young should be waking up for feeds? I asked our pediatrician multiple times but since she's growing insanely well, our pediatrician told us to just follow her lead and not wake her.

During the day she feeds often, around 8-14 times a day. Usually before and after every nap. In the evening she always has a few hours where shes fussy/gets colicky. She often cluster feeds in the evening. Shes in a cosleeper bassinet next to my bed so i should be hearing her if she wants milk. She is exclusively breastfead.

Im noticing i find it hard to trust that it's really okay to let her just be. I was also worry it would impact my supply not to nurse for 8/9 hours a day but shes still gaining a lot of weight so that shouldnt be a problem.

I was hoping someone might have some insight on this. It's still getting me worried. Thanks so much on advance :-)

Ps I live in Europe, English is not my native language :)