Knowing your child's appropriate developmental stages is important. Although many children met their milestones at different times, there is still a window of opportunity in which they should exhibit certain behaviors. For example, if your child is not crawling by the time he or she is 9 -12 months, there may very well be some underlying issues that need to be addressed.
Like many parents, I was initially hesitant about drawing attention to my children's issues. I was adamant that what they were experiencing was the result of not being around other children, not attending a daycare where they could socialize and develop appropriate communication skills as well as social behaviors. I feared what I would hear if I spoke up during our visits to the pediatrician.
Autism does not go away. Ignoring an issue because of fear or a genuine belief that it's "something else" keeps our children from getting the attention that they need the most. Even if your pediatrician determines that there is no need for concern, it's always better to err on the side of caution. While my children are doing fairly well, I truly believe that early diagnosis could have provided them with a stronger foundation, especially once they entered public school.
Remember, talk candidly with your pediatrician if you have concerns about your child's development. Doing what is in your child's best interest is far greater than being paralyzed your fears.