Callisto was like this shortly before she died :? is the rabbit looking upwards a lot or facing or backing into a corner?
It can be a sign of pain or neurological complaint.
Keep a real close eye on her Kris, Calli went down hill in the space of a few hours and the odd neurological symptoms were the first sign...barely noticeable at first and then got stranger and stranger. Also watch her movement and co-ordination.
Hope she will be OK.