Well I think it was, I'm not positive, but it must have been PINK EYE!

The eye drops made the problem go away so Annie must have had pink eye. The puss is gone but she still kind of has a drippy eye. I'm pretty sure that's going away too though so I think she's basically better.

The headband over the eyes has nothing to do with it, just a wardrobe malfunction caught on tape.