Twice now I've fallen asleep on the couch and when I woke up there was a clear "skin bubble" on the lower right, outside corner, of my right eye. The bubble sort of wrinkles up if I push on the lower lid, otherwise it's flat but obviously not firmly attached to the eye. It kind of looks like a blister you would get on your skin. Do I have something wrong with my eyes or is this natural if I might have rubbed it too hard during the night? Maybe I'm allergic to something in the couch. Last time it went away in about a day or two but was really irritating and itchy. I'm hoping it goes away the same way this time too. How common is this? Thanks folks.