Hi, I understand your concern and I'll try to help you. Most head traumas are by low energy and do not bring serious consequences. However, cranial traumas of higher energy can cause serious injuries such as fractures, intracranial bleeding and direct injury to the brain. And these injuries can be serious and potentially lethal. These injuries appear with some warning signals.
These signals after a head injury are
loss of consciousness immediately after the trauma, persistent headache, nausea and recurrent vomiting,
persistent dizziness, confusion, abnormal behavior, liquid outlet from the nose and ears, especially if accompanied by blood. If any of these signs appear immediately seek the emergency room to investigate if there is any intracranial complications such as
subdural hematoma,
subarachnoid hemorrhage, or
epidural hematoma, fractures of the skull base bones and brain concussion.
However, I suggest you take him to emergency room to better investigation and rule out any risk of complications.
Hope I have answered your question. If you have any further questions I will be happy to help you. Wish you good health.