<s>[INST] Hi my son fell and hit is head about 30 minutes ago. He has a big knot on his brow bone. Its a little purple not bad though. Its the hard knot that worries me.and he still has the imprint of the counter top.. he is acting normal but all of a sudden he is saying he is cold. Is this normal? Or do u think he needs medical attention? [/INST] Hello,Thank you for contacting me at "Ask a Doctor". I will try to answer your question to the best of my ability.It sounds as though he has a local contusion to the area. apply some ice, and give him some ibuprofen or Tylenol.  If he has any signs of concussion such as dizziness, nausea, vomiting, drowsiness, etc., then you need to take him to the emergency room. I hope this information is useful for you. Please do not hesitate to message us back if you have any further questions.Best wishes,Adrian Rawlinson MD </s>