As a parent educator, I find that a pediatricians have certain specialties like the flu, colds, etc...
For this, you need to seek out a nueropychologist, OT for the sensory, or a center such as this one TLTC.org---- in CT.
Please do not wait. Sensory usually overlaps w/ some thing else...like ADD or ADHD, etc, etc.
I could write a book about families I have helped that did not know where to turn after seeing their pediatricians!
OT, by the way, is beneficial for all children.
Gum would be wonderful to help the sensory---not for just the chewing--but for the sensory input, too.