Make sure you have a physician check out the whiplash thing ASAP. It often takes a day or two after an accident to exhibit symptoms. This isn't about cynical lawsuit stuff at all. Insurance companies will pay for physiotherapy and other reasonable treatments given a medical diagnosis. 
Did that pronto.  I didn't feel the pain and numbness until a few hours after and saw the doc the next morning.  X-rays were snapped and Advil swallowed.  It takes a few days for the doc to review the pictures but already the sensation is feeling more normal.  If problems present themselves later on I want evidence that I can go after the insurance.  If necessary they can do MRI's.  I've also got coverage at work that covers things like chiropractors and therapy.