Hi J.,
I don't know too much about autism, but there is a website you can check out www.autismspeaks.com
An excerpt from the website:
"Autism Spectrum Disorders can usually be reliably diagnosed by age 3, although new research is pushing back the age of diagnosis to as early as 6 months. Parents are usually the first to notice unusual behaviors in their child or their child's failure to reach appropriate developmental milestones. Some parents describe a child that seemed different from birth, while others describe a child who was developing normally and then lost skills. Pediatricians may initially dismiss signs of autism, thinking a child will “catch up,” and may advise parents to “wait and see.” New research shows that when parents suspect something is wrong with their child, they are usually correct. If you have concerns about your child's development, don't wait: speak to your pediatrician about getting your child screened for autism"
If your doctor is putting you off, maybe you should seek a different doctor who will be a little more proactive in your daughter's treatment and diagnosis. There was a woman on the Today Show a few years ago. Either she or her husband was a big executive of GE which owns Today SHow (NBC). Her grandchild was exhibiting signs of autism and she said they knew something wasn't right because he was developing normally and then "lost" skills, but the doctor kept putting it off as something else. They finally saw a different doctor, but she said that she wishes they wouldn't have waited as long. Good luck to you. {{Hugs}}
K.