Hi Laura,
The langauge that you are using makes me think that you need to get an evaluation that you can count on. Since you said "regional center" I am assuming that you have had a school based, state agency type of free evaluation? If that is the case, and you have not been to a Developmental Pediatrician for a full evaluation, one that takes many days and inludes many different specialists, that generated a report for you that was 15 to 20 pages long (one that either you paid for, or your insurance company paid for) then you really do not kow if your son has had Asperger rulled out or not.
Regional Centers, ECI, and Public School districts all receive funding through the federal government under IDEA, and conduct mandated evaluations on every child who is suspected of having a disablity. They have a clear afirmative obligation, but their purpose is to find, evaluate, and identify children with disablities so that they can be appropriately educated, not so that they will be treated for all issues or conditions that the child may have. They have defined all disablities by thier own standards, ones that are decided by administrators with the help of lawyers who read the case law on these matters, and know when they must provide services fo a child so that they will not be sued. This does not mean, under most circumstances, that your son does not have asperger syndrome, it means that who ever evaluated him was of the opinion that he did not meet their criteria for them to provide services.
The other word you used, "test" also makes me wonder, there is not a test, there should be an evaluation that includes: medical, neurological, occupational, educational, psychological, language, speech, vision, and sometimes gentics, ENT, audiologists and others.
It is not unusual for high functioning children who are on the autism spectrum to be missed in early diagnostics. If you think that there is any possiblity that your child has a developmental issue, call the nearest children's hospital and make an appointment with a developmental pediatrician.
None of us can tell you if your child is on the spectrum. That you are asking, and that you have had reason enough to have him evaluated, and now, your sons kindergarten teacher has noticed something that makes you wonder, get a proper evaluation so that you can say with confidence that he does or does not have an issue. You may find that he does not, but you will get helpful information about things that you can do to help him in ways you have yet to thing about. Evaluation is never a bad idea.
Keep in mind, if your teacher ever suggests that he has a particular disorder, the school is then obligated to evaluate him for that disorder. For this reason, most teachers will not suggest a diganosis. If your sons teacher continues to tell you what she sees, you should have a serious discussion with her about what she thinks and what your son needs to be sucessful. She may not be able to just come out and say what she thinks, because she could get into trouble, but she can help you if your son needs it.
If you get a diagnosis from a Developmental Pediatrican, also request an evaluation from the school.
M.