What is the appropriate age to test if a child has SPD

by Rita
(Cranford, NJ, USA)

I read somewhere that accurate diagnosis of SPD is determined when a child reaches 6 or 7. Is this true? If so, can I already seek medical help for my child who is only 3 if I notice symptoms already? She may have hyper sensitivity to sound because she would close her eyes or cover her ears all the time when she hears loud noises or we are at a party and people are talking or laughing out loud. She would try to go to another room and avoid the loud commotion. If I try to stop her from leaving the room she would cry and become hysterical.