My DS is totally opposite. He is a HUGE sensory avoider. He hates hugs and kisses and being touched (although he is much better about it now). He also had (and still has to some extent) epic meltdowns. I went about things in a different way (b/c I did not know any better). We started with a social worker to help DH and I parent better. Social worker sent us to a child psych. Child psych said she felt DS's issues were neurological an psychological. Off we went to the OT and finally to a developmental ped. We started at age 3.5 and by age 5.5 DS had an ADHD diagnosis with SPD. Dealing with DS everyday is HARD. Honestly it sucks all of our energy.
I would definitely let them do an informal eval. Depending on what they find I would probably go the next step to a developental ped.