Head size doesn't mean much in birth hun. I hate when people who are sposed to be medical professionals do that! What a twit! Wonder if she's even had kids.
My last had the biggest head of my 3 with not even a graze, where as my girls heads were the same size & my tear was worse with my 2nd than it was with my 1st.
I've not had a stitch yet & my babies weren't real small!! There's no real way for anyone to know the actual size of your baby til its born. Not weight, HC anything.
Trust your body. It was made to birth your baby