My son slipped and fell on a metal bar at the playground. 12 hrs later swelling decreased, but bump still there. what should i be looking out for?

Where is the bump?: It is difficult to answer this question accurately without knowing that.If it is on his head, the bump can last for several days. Also, you should check for a sunken in area under the bump, vomiting, lethargy, other unusual behavior. Please seek immediate in person medical attention if those occur. If the bump is elsewhere, please re-submit your question.Call his doctor if concerned.