You don’t have to hit your head on something, or to have something hit it, to suffer a concussion. In fact, you can get one without your head even touching anything. Sudden, violent movement of the head or upper body alone can cause not only whiplash but also a concussion. But falls are the most common cause. Symptoms include headache, ringing in the ears, nausea, vomiting, fatigue, and blurry vision. Outward signs you have a concussion include slurred speech, slow response times, and forgetfulness. You may or may not lose consciousness; most people do not. But you may feel confused or dizzy or you may suffer amnesia. Most people usually recover fully from a concussion.