Not a concussion. Common problem caused by cold water, acute disorientation due to the smack and spin of a wipe out whatever. Sets the middle ear fluids in motion hence the dizziness sensation. Generally subsides in a few minutes but can last up to a day or two. Rarely needs medical attention just rest and recovery. Concussion needs more neurological symptoms like brief loss of consciousness, slight memory loss, impaired cognition, and possible pupil reaction irregularities.
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