Brief Answer:
First 24 hrs is the most important phase..

Detailed Answer:
Hello XXXX, Welcome to HCM,
I've gone through your query and understand your concern..

Well seems like he'd hit his head pretty badly but as of now just keep him under strict observation..

It's good that you've applied cold compression already, continue it with a ice-pack or a bag of frozen peas..

You can give him simple analgesic like Tab PARACETAMOL 650 mg two to three times per day after food for the next 2-3 days..it'll take care of the pain..

Let him rest but keep him awake and vigilant..

Watch for the size and discoloration over the lump, initially the lump will grow a bit, but if it continues to grow even after few hours , then it should be checked out..

First 24 hrs is the most important phase for any kind of head injury..

From your description, it seems like a minor head injury and he may experience mild symptoms of Concussion injury like mild lightheadedness or heaviness , dizziness , tiredness , some tingling sensation over the affected area, ringing noise over the ears..

But if there's any signs like excessive drowsiness, any visual disturbance, disorientation, sudden excessive vomiting, weakness of any part , any abnormal movements of any body parts , speech disturbance , any unequal size of the pupils etc. then you need to take him to your nearest ER at the earliest for a physical examination as well as CAT-Scan of the Head ..

As of now, keep him at home , don't let him do any strenuous activities as well as driving etc.

Let me know how he stays in the due course..

Don't worry, as the symptoms in mild concussion can only be there for a few days depending upon the impact of the force..

Take Care
Regards

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