Ask the Attorney: Injury insurance after car accident

Ask the Atty,
I injured my neck in a car accident and now have neck pain every day. My orthopedist says I have a 6% permanent impairment to my neck. I am only 35 yrs old. The insurance company for the guy that hit me paid his $20,000 policy limit. I have $300,000 in underinsurance coverage but my company is only offering $1,000. Is that fair? What should I do?
Alex R