Martian thread

I'm just a chapter or two away from being done writing my Martian novel. And I have a very weird sensation on one finger, as if there's a thin thread wrapped around it, but obviously there isn't (unless its invisible) It's a wee bit annoying. I'm guessing it's Martian related. Maybe it's the thread connecting me to Martian goings on, like a telephone wire about to be snapped. Who knows?