How long after a hit to the head do you know if there is internal bleeding?

The symptoms of internal bleeding after a head injury can vary widely and may not be immediately apparent. Signs such as severe headache, confusion, nausea, vomiting, or changes in consciousness may develop within hours to days after the injury. It's crucial to seek medical attention if any concerning symptoms arise, as diagnostic imaging like a CT scan may be necessary to assess for internal bleeding. Always err on the side of caution with head injuries.