Go to an osteopath who deals in sports injury. These practitioners closely examine the spin and are very knowledgeable with all the connective tissue and nerves.
With so much injury your tendons and muscles will be scared and knotted and thus causing you pain.
An osteopath can gently massage these areas to release the tension and knots and later if necessary do any manipulation of the atlas area that may also be causing pain. They can also show you how to sit, stand a walk with correct posture to help take tension from your nexk. Dont leave with a load of pills and so forth. And stay away from chiropractor as many don't message before hand or for long enough and can cause more injure to scare tissue.
Combine this with acupuncture, again with someone familiar with whiplash or sport injury. Any Chinese herbs would be very beneficial for pain, so if you walk out with that type of medication you should be pretty right.
Warm and hot compress is also a good idea to help blood flow to your injured area and helps with the healing progress.
All the best,
Agape,
searchingsam.