Without knowing all of the details, it's never a bad idea to go to your doctor if you have even the slightest pain somewhere. Having everything on record might be very helpful regarding future health issues, insurance, etc.. My wife was hit head-on about 15 years ago and the minor aches and pains she initially had developed later into lifelong debilitating health issues. The driver of the other car was unlicensed, uninsured, and driving someone else's car. We also learned the importance of having adequate uninsured motorist coverage on our insurance (MI is a no-fault state).
Thank goodness you came out of this o.k.. Think of the possibilities.