My 7 year old grandaughter has developed small knots on her head. One is near the crown and there s one in the back where the neck and head meet. Also another one on the side of her head. They itch and she said it hurts when she lies down on them. She was bitten on the hand by my little dog last week but it s healing well. The only other occurance is she has been swimming in a neighbors small pool and the water was low and looked like it needed some chemicals. These are the only things I can think of that could contribute. They don t appear as a mosquito or insect bite at all.