Other symptoms of a concussion include confusion or feeling as if in a fog, amnesia surrounding the event, dizziness, or "seeing stars." Some symptoms of a concussion occur right away. But sometimes symptoms may not occur for days after the injury, such as trouble with concentration and memory, irritability and other personality changes, sensitivity to light and noise, trouble with sleep, feeling emotional or depressed, and changes in taste and smell. Concussions can be hard to recognize in infants and toddlers because they can’t describe how they feel. These symptoms include a dazed appearance, listlessness and tiredness, irritability and crankiness, loss of balance and unsteady walking, excessive crying, changes in eating or sleeping patterns, a lack of interest in favorite toys, and vomiting. Also, to diagnose a concussion, your healthcare professional evaluates your symptoms and reviews your medical history. You may need tests to help diagnose a concussion. Tests may include neurological exam, cognitive testing, and imaging tests. For example, your healthcare professional asks detailed questions about your injury and then performs a neurological