I think as you have concerns you should raise them with your paediatrician. He should be assessed by a Speech and Language Therapist, psychologist, and maybe other professionals and they should all be experienced in diagnosing autistic spectrum disorders.
It maybe that he is just speech delayed, but depending on his verbal communication problems a good experienced SALT should be able to give you an indication as to whether you are looking at a possible/probable diagnosis of an autistic spectrum disorder.
It is good that he is verbal and that he is putting his hands out to be picked up and undressed.
By 2.5 years he should be developing his social side, so it is hard to judge at his age. But it is very important that any difficulties he has now are addressed to help him. You could ask the speech therapist about whether it would be useful to learn some signing. Signing will not stop a child using speech and it will help the child communicate and you can be reinforcing the signing by using words.
If he is not playing with toys in the 'typical' way ie. he spins car wheels, stacks things or lines things up, plays with parts of toys instead of the whole toy etc, these are things to mention to your paediatrician.
If you click on the Health Page icon on the top right hand corner of this page you can access the diagnostic criteria behind the behavioural characteristics of an autistic spectrum disorder. This is the clinical criteria under DSM IV that professionals will use to decide if a child is on the spectrum. Parents have also posted examples of their child's behaviour that fits the criteria so that you can have an idea of what the professionals are looking for.
Spinning is something that all children/toddlers do to some extent. Alot of children on the spectrum spin or flap. Sometimes it is excessive, sometimes it is not apparently excessive. They don't have to do it for long periods of time. Sometimes it is something they do to regulate their sensory systems so they might do it inbetween things or they may stop doing something, spin a few times and then return to what they were doing.
Is there any other type of sensory differences you have noticed eg. does he appear deaf, cover his ears at noise, not like socks and shoes, problems with food etc.
Are there other toys he always prefers eg. building blocks, puzzles etc.
Does he come to you for things or is he very self sufficient ie. does his own thing and doesn't bother you at all.
Does he have tantrums if you take him out of the house, or turn off the TV.
What you have posted sounds like normal behavior for an 18month old so you should concentrate on good Paren tchild interaction, Fun and games, not much rough housing,dont read more into it .
If he's a late talker, try teaching him sign language. There is "baby signlanguage" as well, which modifies some of the signs for small children to be able to do, though most of the signs are the same as ASL (I think that's the american sign language acronym)...
Anyways, lots of parents are teacing their kids sign language. It takes them longer to learn the first few words... but most kids like to use the words more, milk, and eat as their first 3 words. There are a lot of books on teh subject, and you have to be serious about using sign language -- usually it takes several weeks to get your child excited and into signing... you have to use it repeatedly during play and at mealtime. Sign language can be really empowering for children. Many will use the sign "more" to mean they want whatever it is they want in the first place. Please is another good sign to teach, so kids can ask for something.
I doubt I can offer you much different but this is my advice. I have done the Autistic mom thing for many years. When my son was diagnosed no family md's could or would make that diagnosis. And I still believe they should NOT. Childrens hospitals use panel of dr.'s that when done all come together and make a much more accurate diagnosis. The so called spectrum is in my opinion a joke and it is my belief many children are unduly diagnosed "autistic". Many more are not....I can tell you only my experience and that is this...
at about 17mo's old my son STOPPED saying Mama and any other of his learned words, he sat near the wall and would tap the back of his head against the wall. He would fixate on certain toys with utter redundancy, and at first (due to an ear infection) I thought he had lost his hearing!! Later I realized he did not. I hid in the hall where he could not see me and whispered his name and he turned looked and came to me....But if I spoke in a reg tone or even a little loud it was like he totally could not hear me....Strange I know but none the less true... At age 5 he finally began talking again and then instead of mama or mommie I was then Yammie. Later I became Onnie then finally about age 7 or 8 I returned to being Mommie! He is 16 now and started pointing at age12. Big deal for us was this.....If he didnt look me in the eyes I put my finger on my nose and if he still did not he did not get what he wanted. Now it has been 5 yrs since I have had to touch my nose..... Best of luck!
It is a little early to tell if your son has autism. Autism is diagnosed in a spectrum. some children have a few symptoms, where others demonstrate many of the symptoms.
Interaction and language are key. One of the typical things that happens in autistic children is that they gain language, then they lose it. For example, my son had more language skills at 2 than he did at 2 1/2. In some states, you can get free speech services through the public school district.
After he turns two, have him assessed by a group of trusted specialists in your area, ask your pediatrician for a referral for further testing.
Remember that everyone is an individual and their potential is unknown. My son is now 16 and in high school. He has been in standard, regular classes his entire school career. He has friends, goes to school dances and is doing great!!
18 mos is a little soon to diagnose anything for sure, but what I can say is that children should have a vocabulary of 25-50 words by the time they are 18 months, so if nothing else, this child needs language therapy