My husband is 48 years old last week while coming back in the flight he had severe pain on one side of forehead which went upto head further, he felt as if his nerves are being pulled severely then after a while it reduced and cooled down. He came home had his dinner and slept next day morning he felt better. He is following his normal routine but still feeling some strain and pull of muscles on one side. Please advise what to do is it a sign of something serious?