Frustrated at breast

Me
Does anyone else's newborn tug and pull really hard on your breast while nursing? Mine is 3.5wks and halfway through nursing he starts to and it looks like he gets frustrated too and starts to cry. Am I holding him wrong, does he need to burp or is this a sign to switch him to other breast? I know he's getting enough nursing from one side bc I produce a lot. Or is this just normal behavior