Could my child have Autism

My son is 5 yrs old and ever since he could, he gets on all fours and rocks back and fourth and hums. He also takes his thumb and like counts all of his fingers real fast. Also, when he stands still he shakes, he is very hyper active and gets very loud for no reason. could it be Autism?

[Jessica L Thomason Sassi, Ph.D., BCBA-D]

Although one of the diagnostic criteria for autism spectrum disorders is highly stereotyped or repetitive behaviors (like body rocking, hand flapping, etc.), two other criteria must also be present: delays in language and impairments in social interactions.  Many typically-developing children engage in stereotyped behaviors at some point, so keep in mind that (rocking) alone isn’t necessary an indicator of autism.  Your description doesn’t really address his development with respect to language acquisition or social skills, which makes it tough to say whether your concern is warranted.  In any event, in-person evaluation by a professional is necessary for diagnosis, so I would recommend that you describe your concerns to your pediatrician and ask for his/her opinion on whether your child would benefit from referral to a specialist.  
Good luck