OMGoodness! i am having the exact same problem. it's a large swelling that occured over night and the left side of her face, well kind of a bit under it is swollen just like the pic. if anyone has any idea please help.
another interesting thing, yesterday i saw behind her ear what looked like a little blue thing. almost like a big swollen tick, but it isn't a bug i dont think. it's also attached to that huge swelling.