Baby weight questions

My son is 2 weeks and 1 day old he was born 8lbs and 4 oz. he is strictly breastfed and has had trouble gaining his birth weight back he is currently 7lbs 9oz. We’ve been going to the doctors almost everyday some days he’s gained some days he’s lost an ounce or some days his weight is the same. Has anyone else experienced this? Doctors are pushing for formula but I don’t want that for him yet I’m currently pumping and now giving him breast milk in the bottle any advice or input would help I just wanna know if this is common and not feel like I’m doing something wrong!