Lara,
your c1 & c2 the top spinal vertebra could have gotten misaligned from the injury.
some info on that-
http://www.upcspine.com/self.htm
http://www.uppercervical.org/subpag...b/about_faq.php
http://www.spineuniverse.com/index.html

spinal chart
http://neurotalk.psychcentral.com/post284498-35.html


I was also having some vertigo/dizzy spells last August and it was due to chronic sinus allergies - the Veramyst nasal spray and a week of allergy tabs took care of it.