There could be many things covered by what you describe, it could be an Autism Spectrum Disorder (ASD), it could be a social communication disorder (SCD), it could be learning difficulties...to accurately diagnose can take months as they usually need a team of professionals (Paediatrician, Speech & Language, Occupational Therapy, Audiology, Education Psychology...) to assess & report back. They may want blood tests to rule out chromosome defects. They may look at family medical history & any issues that occurred with the pregnancy & birth.
All I can say for certain is you have taken the first step to getting answers. Good luck on the road ahead, it can be a long one. X