I'm not sure what they are, but there are small bites (like insect bites, not dog bites or something) on my left leg (on my calf) in the shape of a 3. They're about the same size as mosquito or flea bites but all connected, they itch as well, but not all the time, only maybe once every week or so. I thought they'd just go away but they've been there for at least a month, probably more. What are they?