My rabbit sways her head back and forth all the time is that normal?

Is this just when she is sitting or lying? It can indicate an issue with e-cuniculi(parasitic infection that can cause brain damage) or vestibular nerve problem caused by an ear infection or past infection. Some (mostly the pink eyed guys) will do this (scanning) due to poor eyesight which is not indicative to any problems. If this is something new take him to your vet for a look over.