Green stuff around my bun's nose

[Scarlette]

My bunny has a greenish tinge around her nostril, Any ideas ?
(Sorry about the bad pictures its hard to take a photo of a moving animal)

 

[JBun]

Could be pellet or hay dust. She hasn't seemed to have a choking episode at all has she, such as acting oddly while eating pellets, like odd mouth movements, head held up in the air, foam or bubbles coming from the mouth or nose, or suddenly darting around frantically?