I also have a TBI and I read your concerns. I found out after 6 3/4 years that my brain injury has affected me in a numerous of ways. The best advice that I can give you is to tell your nuerologist about what is going on and never give up hope. I have suffered so much from being miss diagnossed that finally I found some realy good doctor's and also found a lot of my own research onthe internet because personally I though tthat I was going nuts. There are also nueropyschologist who can test you to see what part/ parts of the brain also is injured. The best test to determine a brain injure is a PET scan. MRI's usually don't pick them up and neither do a CT scan.
I have lost a part of my memory and also face other health issues due to my injury and it all comes over time. Alot of it is treatable as long as you stay strong and keep reminding yourself not to give up the battle. It is a long road but have faith and you will make it.
First of all, keep in mind that I am unable to diagnose you because I am unable to examine you, this forum is for educational purposes.
It is possible that the headaches, balance problems and confusion are all due to migraine headaches. These are common symptoms and migraines are usually at their worst in the 30's for females. I would suggest that you start a migraine preventative medicaton such as Elavil, Topamax, Nadolol, etc. daily to see if this improves your headaches. However given you complaints of jerking etc, I would suggest that you evaluate more for seizures. Trauma to the brain during a car accident, most frequently involves the anterior and middle frontal lobes, and anterior temporal lobes (as well as a diffuse axonal injury). The damage to the frontal lobes can give rise to strange atypical seizures that are hard to spot on the EEG, because they are deep in the brain. In addition, routine EEGs are only 20 minutes long and patients often do not have there jerking/confusion spells while getting the EEG recording (thus it would be missed). I would suggest a longer, sleep deprived recording that is albe to capture one of your spells (you may need to be admitted to an epilepsy monitoring unit for several days for this). A PET scan may also be helpful by showing an area of hypometabolism (where seizures may come from). In light your symptoms that may be due to siezure or migraine, Topamax, neurontin, lyrica, etc may be your best choices (they work for both) until you can have your prolonged EEG. I hope this has been helpful.