You might want to consider visiting a speech language pathologist in order to address this concern. An SLP will run you through certain set of questions to get a best idea about your child and also observe the child's skills in various settings. A standardized assessment typically helps to understand the lag in child's communication skills which further helps to formulate goals tailored to the need of your child. If the SLP feels there is a need for more professionals to intervene, he/she will accordingly refer you for further evaluations to help you in the best possible manner. The early issues are addressed, the better. Good luck!