Answer:
Difficulty breathing
Step-by-step explanation:
According to the Mayo Clinic, a reputable source of medical information, the following could all be symptoms of a concussion:
Headache
Ringing in the ears
Nausea
Vomiting
Fatigue or drowsiness
Blurry vision
Confusion or feeling as if in a fog
Amnesia surrounding the traumatic event
Dizziness or "seeing stars"
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
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
The majority of these are issues with cognitive function or brain issues, not affecting breathing. Hope this helps!