I think you could approach the doc the way you told us about it--factually with the comparison to your sx and the fact that your son does not complain.

There's nothing wrong with being concerned for your child. If those fears turn out to be unfounded that's great, but if not, then you acted prudently. And even if they were unfounded, given your personal experience, you acted prudently.

Being hysterical or paranoid as a parent means running to the doc for every little tiny thing and demanding testing. You're NOT doing that. So who cares WHAT a doc might think of you. This is your child's health and that's important and within your right to look after.