My medical issues from a MVA at my last job are not improving and now I have new issues. Should I consider a lawsuit?

I was rear ended while driving as part of my job duties at my last job. I ended up with a concussion, post concussion syndrome, and ringing in the ears and vertigo. I also had something where a cervical vertebrae was locked up and I could not turn my head to the left and had to have physical therapy. I was out of work for a month then went back PT for another month. I was on medication for the ear ringing and vertigo, pain med, was in a lot of pain and could not drive for a month. I also had severe issues with memory and concentration which have continued and are so bad I have had to start ADHD medication. The vertigo and ringing are almost completely gone. Recently I spontaneously had my 1st ribhead dislocate in my sleep on the same side my neck issues were and now am having pain and tingling in my arm and fingers. Chiropractic manipulation is not working and I am wondering if it is related. The memory/concentration issues are still a big issue. I ended up leaving a job I loved because I was falling behind on work I used to be able to do and having to sit up all night at home to do it. I was suddenly angry all the time- people say I am a different person since this concussion. I do have fibromyalgia and have had for years but it has been well under control and not interfered with my work at all, so that worries me too. My work was good to me and paid my salary so I didn't do anything. But I am worried I won't be able to do the same level work again and will always have to take this ADHD med. Should I sue and is it too late?