Suggest Remedy For Raised Red Irregular Size Blotch In Forehead

My doughtier is 9, several days ago found what looked like a small round pimple that had been scraped off and there was a dried yellowish scab over it. It was just in her hairline on the forehead. 3 days later it has a raise red irregular size blotch the size of a nickel. It has raised tentacle like red stripe going down her forehead. It is hard and she said it hearts a bit when I touched it. In the center there is a small crater-like indentation that was left from original site. It looks like a bight of some sort. We are currently in Poconos mountains in Pensilvania on vacation. She says that she did not hit her forehead or remember anything biting her during the day. I put Neosporin on it now. What could it be? Should I watch it or take her to a doctor?