Is breastfeeding not common in your area? This is the only reasoning I can think of why maybe they aren’t familiar with the breastfeeding standards. Feed your baby on demand how much ever he needs!!! Mine is 6 weeks old and 12lbs. He was born at 7lbs 9oz! The doctor laughed at how I was probably not getting any sleep because of how well he’s gaining.

https://www.llli.org/breastfeeding-info/frequency-feeding-frequently-asked-questions-faqs/

I’d switch pediatricians just because of how he treated you. You are this child’s mother and you absolutely don’t deserve to be dismissed and patronized.

Feed that baby to his little hearts content!