As you identify concerns about child development, you'll use assessment to a. evaluate whether a child has a special need or disability. b. support developmental screening results and determine whether to refer children for further examination of evaluation. c. talk with other professionals to determine whether the child has a disability. d. document children's growth and development.

As you identify concerns about child development, you'll use assessment to C. talk with other professionals to determine whether the child has a disability.
I think that  you should talk to professionals before making your own decisions about your child. What if you're wrong about your assessment and then you ruin your own child's life and health? It's better to be sure before taking such extreme risks.