Depending where you live, but there are some great services which offer short courses for children to help with disorders like this. A lot of programs tend to be commuter based too but I would start early on help as you will be helping your little guy to minimise the distractions.

wow i had not ever heard of this before. maybe google it or start a forum to chat with others about it

I agree with seeing a OT. Check out your local services and choose one that specialises in kids. My son is currently been assesed for simular issues he is 6 years old. Once you have choosen one you should be able to get a refferal from you doctor to help with costs. They can also help with activities that can help your son.

I second the occupational therapist. I would assume getting help early is better than waiting for him to be old enough to diagnose before doing anything. Get a second opinion from a doctor as well.

Gst a referral to a pediatrician who can then get you onto a plan to assist with costs of occupational health etc. The sooner the better

I strongly advise going to see a private occupational therapist or if uou can not afford it at public one, the earlier the better

An Occupational Therapist may be able to assist you with possible activities and strategies as it does depend on the type of sensory activities that your son finds overwhelming. Many people have sensory issues and an Occupational Therapist may be able to assist you and your son with finding what ‘works’ for him. Processing many people and lots of different information can be so overwhelming when you have sensory issues. Good luck!