It does sound like stridor which is when there is something present in the airway such as a piece of feed, mucus from a respiratory infection, or swelling in the airway. The sneezing is probably more related to a respiratory infection. I would watch her, and make sure that she is drinking fluids. Sometimes stridor goes away in a few hours or overnight if it is just a piece of feed. Look for any nasal drainage or bubbles in an eye, which are more signs of an infection such as mycoplasma. It looks like she is molting, and that is a common time for something like this to happen.