What is wrong with my chick?

I have 10 chicks that are two weeks old and 1 barred Rock suddenly started staying by herself more than the others do. I then noticed she was getting little feathers,feed, and bedding stuck around her eyes. Then I noticed her eye lids/ skin around her eyes was bigger than the other chicks and her eyes are sort of crusty/ watery. Also she doesn't usually open her eyes all the way and they are almost a milky color. I also think I heard her sneeze. What is wrong with her & it's obviously not contagious because none of the others have gotten these problems and I don't think it's deadly or she would have probably died by now. Anyone have any ideas/ treatments. Thank you!!