Breastfeeding mothers should always consult a lactation consultant when there is a question about whether or not nursing is going well. The current weight charts are based on studies done from the 1950's through the 1970's that specifically excluded breastfeeding infants because that was not considered normal or optimal at that time.

I've gotten the completely wrong advice from pediatricians, even breastfeeding supportive ones, because the information was based on formula-fed infants.

And don't trust your mother either, even if she did nurse, it was counter-cultural and her information is also based on formula-feeding.

I'm a firm believer in going by the baby. If the baby is thriving, alert and interested and active, and has lots of wet nappies and yellow poo, then the charts mean nothing.