V.W.
How recently?
Any chance she got something up it?
My 2 yr old once got a small clear button (I still don't know where it came from) up his nose. It was WAAAYYYY up there. We only knew because he cried and his nose made a funny noise, if I remember right. When I looked up it I wasn't even sure that there was anything up there. After trying and trying... I finally pushed one nostril down and asked him to blow really hard. The button came flying out. It was one of those tiny tiny baby buttons off of some 3 month old baby garment.
It's just a thought... it could be a fly or something that got up there... you never know.