I have a very small slightly raised rash on my arm with black hair-like specs in it. It will not rub off or cannot be "tweezed" out. It's almost ingrained in my skin. Could it be black spot poison ivy? From what I've read that takes on a more tar-like appearance. It does not itch at all and has no pus filled pustules. Any clues as to what it is? I did hand a hibiscus a couple of days ago that had this strange fungus-like bumps on it.