I Had A Concussion About Two Months Ago Involving A

I had a concussion about two months ago involving a motor vehicle flipping over. Since then my left eye twitches/spasms repeatedly every time I look down. My eye doctor blew it off as stress, but this has never happened before the accident. I also had major migraines after the concussion, which have become less frequent since finishing college a month ago. So I assume those were due to stress. But the eye spasms still continue. What could be causing the spasms besides stress?