Every few months at times when I get stressed, I notice red marks that appear around my mouth. They do not look like sores, only red spots on the skin about 1/2 inch or less from the lips. They are about less than 1/2 the size of a dime in diameter. They are usually there for a few hours and then disappear only to reappear in a different spot later. They feel slightly itchy and hot. They will appear in different areas around the mouth and the episode lasts for about 3 days. I've been blood tested for herpes and received a negative result. Also, sometimes there is redness under my bottom lip that also goes away after a few hours. I have pointed it out to friends and they don't think it looks like cold sores. Any idea of what it could be? I always freak out and think whether I could have caught something recently. Last week I drank from a dirty cup at a party and wonder if that could have caused the rash, but I have also been very stressed lately by events in my life.