So this is the first injury that any of my boys have sustained in the 3 years we have had them. They have been pretty easy so far. Yesterday I noticed my boy has a nasty cut behind his ear. It looks to be about 1-2 inches long and is full thickness behind the ear. I cleaned it off with a wound cleaner. Anything else I should worry about? Should I give him an anti-biotic? Here is the best pic I could get of it.