Excessive blinking after trauma

My son is almost 4. He fell approx 3 weeks ago off the couch onto the floor on his neck/shoulder area. He was able to move is neck and all extremeties after the fall so I thought all was well. The next day he was still c/o of stiffness and my husband insisted that I take him.  I called pediatrician and got an order for x ray. X ray taken- nrm. Later that night my husband called me at work stating that my son was blinking excessively. Husband brought him to ER. ER doctor saw him and I insisted on CT scan. CT scan was nrm. He said to watch the blinking and it should go away. NOW, the excessive blinking has gotten better, BUT when my son "becomes upset" about something or "gets in trouble" he starts the blinking again and c/o his head being "hot". NO fever - have checked it. I believe his head is hurting him. He has no idea he is doing this. I have never made it point to "bring attention to it". I have decided to take him to eye dr.. After that I will take him to ped and have exam and documentation to get him in to see neurologist. Is there something I am missing?? Could this be some sort of optic nerve damage? Please help.......