That doesn't look like wry neck, but it still could be neurological. Could you post a normal picture from the side? In this picture she looks like her backend is up high like when they are laying. Have you checked inside her vent (rubber glove, lubricant, insert finger 1-2 inches gently) for a stuck egg?
She isn't sitting quite the same today! She is very skinny all bones! We just bought her and two others yesterday. However we did not notice anything was wrong with her until we got her home! The lady we bought her from had the chickens in a box when we arrived. She did take them out, but we didnt hold her.She does sit forward a lot.
Is she of egg laying age? Get her on some poultry vitamins right away, or some PolyVisol without iron 2-3 drops daily by mouth. I would watch her eating and poops because she could also be showing signs of coccidiosis.