The signs and symptoms of a concussion can be subtle and may not show up immediately. Symptoms can last for days, weeks or even longer. Common symptoms after a concussive traumatic brain injury are headache, loss of memory (amnesia) and confusion. The amnesia usually involves forgetting the event that caused the concussion. Physical signs and symptoms of a concussion may include: 
Headache
Ringing in the ears
Nausea
Vomiting
Fatigue or drowsiness
Blurry vision
 Other signs and symptoms of a concussion include: 
Confusion or feeling as if in a fog
Amnesia surrounding the traumatic event
Dizziness or "seeing stars"
 A witness may observe these signs and symptoms in the concussed person: 
Temporary loss of consciousness (though this doesn't always occur)
Slurred speech
Delayed response to questions
Dazed appearance
Forgetfulness, such as repeatedly asking the same question
 You may have some symptoms of concussions immediately, and some can occur for days after the injury, such as: 
Concentration and memory complaints
Irritability and other personality changes
Sensitivity to light and noise
Sleep disturbances
Psychological adjustment problems and depression
Disorders of taste and smell
 Symptoms in children Head trauma is very common in young children. But concussions can be difficult to recognize in infants and toddlers because they can't describe how they feel. Concussion clues may include: 
Dazed appearance
Listlessness and tiring easily
Irritability and crankiness
Loss of balance and unsteady walking
Excessive crying
Change in eating or sleeping patterns
Lack of interest in favorite toys
Vomiting
Seizures
