She doesn't seem to be in any pain and happily eating. I had a feel round her head and there is no heat , pain or softness. Whatever is causing it is within the skull. The eye is watering but she isn't distressed.
My vet isn't always in so I can't just turn up, usually I can wait all day just for them to return my call. Plus I have to catch her and get in trailer! I'm betting she plays me up when I go back.