Visit your Doc, get some X-rays to check your spine alignment as well as for any small fractures. Especially look at the curvature of the spine through your neck (yes its supposed to curve). Maybe even have your Doc rccomend a GOOD Chiropractor to check for soft tissue damage that he may miss. At least have a GOOD Chiropractor check the X-rays.
I was rear ended 4 years ago by someone not paying attention. I was in my Bronco II, he was in a Jeep Wrangler. He hit me while I was stopped at a red light (he also missed that the lilght was red), rear ended me at over 40mph. Luckily I had no broken bones, I was just sore. I went to the emergency room where the ER Doc diagnosed a back sprain (the insurance companies best friend that Doc). Though he did say that if I still hurt in a week to see my reglar Doc. I still hurt so I did visit my GP and he ordered X-rays. The good news was no fractures. The bad news was that my entire spine was out of place. From the Sacrum to the base of my Skull. He recommended a Chiro, backed up by some of my own research, and it has made all the difference. I do have a permanent back injury but I have come a very long way in the last four years. My Chiro and Neuro-Muscular massage therapy has dropped from 2-3 times a week to once every 4-6 weeks.
The opposing insurance company insisted that we use the ER Docs diagnosis. The ER Doc talked to me, looked specifically for bruising and nothing else and then left. The ER Doc saw me for two minutes (no exaggeration). I had multiple witnesses to that and the opposing insurnace company soon backed off wanting to only use that diagnosis.
I was barely able to get the opposing insurance company to cover my medical bills but they did (just). My Bronco II was totaled, which is how I picked up my TR8. The TR8 is very comfortable and does not casue my back to act up. My TR6 though... I have to "recover" from every drive for a few days before I can get back in it. Which really REALLY sucks.
My current "treatments" are considered "maintenance" and are not covered by Insurance.
Bottom line, get yourself checked out beyond your own satisfaction. PeterK's and my situations are not fun. Do your best to avoid it.