worried about autism

I'm a very worried mom about my son. he'll turn 2 years next months and is a bit behind with his speech but at home we speak 2 languages. we started speech therapy few weeks ago and I feel that my son has already improved and learned new words. My question is, is it possible that some kids with autism lose suddenly their words at 2 1/2 years, and one more thing, does all kids who spin and stim end up diagnosed with autism coz my son seems like evry other child exept for the quirky things he does with his eyes. my son isn't very sociable with kids his age but likes to play alot with us , his parents, he is also very affectionate and ask for water and milk and food. he also immitates us a lot and loves pretend play.i would really appreciate if u help me because I've been worrried about him since he was around 18 months. I even got him tested and the result was that my son is still too young to be diagnosed so basically i have to go for the wait and see approach which is very hard.

[William L. Holcomb, Ph.D., BCBA-D]

I think that it is understandable that you are concerned, but it also sounds like you are closely monitoring your son’s developmental progression and have the correct people involved.  Parents have reported that some children were developing completely normally until a sudden loss in language and social skills at ages varying from two to three years.  This is just one of the controversial topics in children diagnosed with ASDs.  It seems more likely that children who eventually go on to be diagnosed with an ASD were showing signs of delayed and/or disordered development in social and communication skills, but these were not noticed until they reached some “threshold” where a caregiver or professional noted them.  As far as stereotyped behaviors (often referred to a “stimming” or “self stimulation”), everybody engages in these behaviors.  It is often a matter of how often, how intensely, where, what it is and at what age that determines whether it would indicate a problem behavior or not.  I encourage you to continue to keep a close eye on your son’s development in conjunction with your health professionals.  You may wish to look at some of the following websites for additional information about early indicators of ASDs.  

About.com Pediatrics
http://pediatrics.about.com/od/weeklyquestion/a/04_signs_autism.htm
American Academy of Pediatrics
http://www.aap.org/healthtopics/Autism.cfm
First Signs
http://www.firstsigns.org/