Is there any pattern to when it appears (for instance after a shower)? It could certainly be a warning sign from your body- or if you have sensitive skin, it could just be something that's triggered by a small thing in your environment- for example, after a shower if the water is too hot, or if there is something in the air that you are sensitive too. I'm always a big fan of getting things checked out- just in case, but likely it's something in your environment that your body is just sensitive to.