Whip lash can show up hours days or weeks later. Fractured bones in football injuries show up when you get older+, then you find out when it is to late. Trauma is hard to diagnose shock sets in first then your body goes thru the healing process. It is better to have Xrays now than later if you feel pain. Insurance companies want to settle for nothing and fast. You have 2 years in most states to settle or sue for damages. If you think the car is worth $20,000 dollars then fight for what you think it is worth, Replacement cost is another argumentative subject when you get into cars that are have limited production and you think is rare and worth more than a Volkswagen bug. I have been in these kind of settlements. Do not rush into settling.