You most likely had a whiplash injury. It is a term that describes neck pain that is caused by an energy force that is transferred to your body. The neck and head bend backward and forward, like a whipping motion.
Three-fourths of people who have whiplash will completely recover by 12 months. A small percentage of people will have chronic moderate to severe pain in spite of physical therapy and a regular strengthening exercise program.
Chronic pain from whiplash is more likely due to facet joint injury or less commonly, disc injury. Facet joint pain can be diagnosed by specific injections. If it is determined that facet joints are causing your pain, there is a treatment called radiofrequency ablation or neurotomy available. If the facet joints are not the major source of pain, most likely the disc is. A fusion surgery may be considered.