Sorry, too late
This is not intended to be legal advise or as legal representation. I am a California personal injury attorney . Be aware that every state has its own statute of limitations; and statutes & case laws that govern the handling of these matters.
Statutes of limitations in civil law define a period of time during which a claim can be brought. After that time period passes, the claim is extingished. Statutes of limitations are established in state law and vary from state to state. Here is more on statutes of limitations and the policy behind the law limiting the time period during which claims may be brought: BLUE LINK BELOW
Law Offices of Andrew D. Myers, North Andover, MA & Derry, NH provide answers for informational purposes only. Actual legal advice can only be given by an attorney licensed in your jurisdiction, thoroughly familiar with the area of the law in which your concern lies. This creates no attorney-client relationship.
Unfortunately, the time for you to file a claim expired 3 years after the incident. The time is extended for minors-which doesn't seem to apply in your situation.
Unless the brain damage can be demonstrated to have been a disability making you unable to bring a lawsuit, and has recently cleared, you are beyond the statute of limitations.
If you found this "helpful" or "best answer," please click it with my appreciation. My response is for educational purposes and does not constitute legal advice nor creates an attorney client relationship which requires all the details and a personal conference.
Unfortunately the statute of limitations has run, if you were a minor or hospitalized, there would be opportunity to toll the statute but that appears to be inapplicable here.
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