I'm sorry to hear about your accident. Sounds like you're getting mixed messages. I'm no doctor either but sounds like you may have PCS.

First off, concussions don't always show up on MRI's or CT scans. They could both be negative and you could have had a severe concussion. Those test are mainly looking for an acute bleed in the brain. Just because it isn't bleeding doesn't mean that there has not been trauma.

Your symptoms show that you do have effects from trauma. Did you have migrane headaches before your accident? If not then I would have to say its PCS.

PCS symptoms don't always start immediately after trauma. Those that you mentioned I have had. This is really serious. Please go to a DR. that takes you seriously. You could have a long healing process and it is very important that you know so you don't reinjure your sensitive brain.

I experienced headaches that were both tension and migrane from my accident. Everyone is different, and to be honest my neurologist didn't explain it very well to me at first. Most people have a combination of these types. This is important to the doc because pain medications may be given related to what type of headache you have.

Also, don't exercise at all. Especially until you know what is going on. You will feel awful after and may cause more damage. It's hard not to do anything active but just wait.

There is a head injury survival download somewhere here on the site.

Best advice- you have to rest as much as possible and go to another doctor to get better medical advice!

Best Wishes.