There's no harm in taking him in for an evaluation.
There are several things to keep in mind for this. A pediatrician treats childhood illnesses. They aren't up to date on mental health issues and ADD/ADHD is a mental health issues. Although many pediatricians do treat ADD/ADHD they aren't really the best to do the evaluations to determine what's going on with your child.
All psychologists do not do evaluations for childhood mental health issues either. Nor do psychiatrists. A psychiatrist usually only sees their patient for a few moments every few months to refill their prescriptions. They don't do other things as a general rule.
A psychologist trained and certified to do evaluations is what you need or to take kiddo to a nearby children's hospital where they have a children's clinic specifically dedicated to doing this sort of evaluation.
We had a psychologist who specialized in diagnosing children's needs do our initial evaluation at the local health department. Then we took him a year later to Oklahoma University Health Science Center (was called Children's Hospital all my life but O U bought it out and renamed it). We took our boy there and he spent the day. We got to sit behind mirrored windows for a majority of it.
We watched the psychologist go through lots of things. From having to verbally tell what an item was for, such as what do you do with shoes, to copying a pattern with bi-colored blocks/cubes half red and half white on a diagonal. Then a physical therapist evaluated him for gate, running, walking sideways, and so much more. There were physical evals along with hearing, sight, and color blind stuff. He spent the day having fun, it's not like sitting at one spot and having to answer questions. They had swings built into the ceiling, a playground outside where they observed him climbing, swinging, and having fun for about 20 minutes a couple of time.
They had the teachers fill out evaluations, both hubby and I filled out our own , independently of each other, and anyone else that had daily contact with kiddo. With all the information they came back with a fully comprehensive evaluation where we could see where he was developmentally and for health issues like bowed legs and pigeon toes to having ADHD. He was very high in a couple of areas, normal in some, and low in others that we hadn't noticed at all. Having all this information we were able to get him special help at school through having a 504 plan. He got pulled out of class to do reading and a couple of other things. Once he got the skills he needed he was able to be up to the level he needed to be.
Getting your child evaluated is a great thing because it gives you the best basis for helping him individual help in his areas where he needs help.