Hi there!
Please don't fret sweetie! 35oz is a LOT of formula. In fact I believe 24-32oz is what is rec. Some take more, some take less. Here is a link about amounts:
https://babywhispererforums.com/index.php?topic=67933.0 I personally think 20-25oz is fine, especially if baby is gaining weight steadily. I also believe in listening to your baby and letting him guide you, as you are doing.
Are you doing EASY? At 6w you may consider feeding every 3h during the day, tanking up before bed, doing a dreamfeeding, and then feeding as needed through the night. I do not think you need to go crazy trying to feed him very often because often times, they will take less because their tummy never gets a chance to expand from taking a bigger feeding.
I think you should use a bottle and nipple that you and he are both comfortable with. Burp frequently, and offer him as uch as he wants at each feeding.
It's hard to know what's best, we expect our pedi to guide us and for the most part they do. Sometimes though I think they forget what it is like to be a first time parent, they forget that every single thing they say to us, we take as very seriously - so sometimes they may not be as supportive and understanding as they could be.
Big hugs to you, you are doing perfectly. Sit back and enjoy this time with your new baby - it goes by so fast.
