How can you tell if you have whiplash after rearending?

Symptoms. Whiplash is non medical turm from cervical acceleration -deceleration injury-usually neck pain radiating to shoulders with pins, needles in arms can occur from multiple mechanisms like falling without even rear injury--symptoms resolve by themself within few weeks except for small group of people.
Sore neck. You will have a sore neck with stiffness and pain. Difficulty moving your neck etc. A formal course of physical therapy along with NSAID ( Motrin advic etc.)is warranted.