hi thanks for query this was not seems to be due to minor head injury you should rule out causes of blackout. Blackouts are periods of unconsciousness or memory loss. Generally, a blackout is described as a period of unconsciousness or lack of awareness when you are unable to recall what happened or what you did. Blackouts may occur as a result of brain damage, drug side effects, or disorders affecting brain function A generally harmless form of blackout is known as vasovagal syncope. In this condition, there is a disruption in the balance of neurotransmitters that regulate the blood vessels and heart rate, causing a temporary decrease in blood flow to the brain. This is a common cause of fainting that may even occur as a reaction to stressful or frightening situations. Blackouts can also be due a recent traumatic event, in which case you may forget everything that happened right before or right after the event. Unexplained blackouts, or blackouts that appear to be due to injury or trauma, should be evaluated by a doctor