I noticed a small red bump on my finger yesterday. It looks like an ant bite, but it doesn't itch, and it only stings a little when touched. Today, I realized I have three of these on my feet as well. Same thing: no itch, slight sting when touched. I've scoured my bed, but I haven't found any signs of bed bugs. I haven't eaten anything unusual, so I don't think I'm having an allergic reaction. Any idea what these could be?