Headache
Dizziness or balance problems
Nausea or vomiting
Confusion or feeling dazed
Memory problems
Trouble concentrating
Blurry vision
Sensitivity to light or noise
Slowed thinking or responding
Feeling unusually tired or sleepy
Irritability, sadness, or mood changes
Loss of consciousness, even briefly
Symptoms that worsen over time
Seek urgent medical care if symptoms are severe or you suspect a concussion after a head injury