Does she have other symptoms that could be from a respiratory disease such as mycoplasma (MG) or coryza? Does she smell bad? Those would be nasal drainage, coughing, wheezing, gasping? Could she have been stung or pecked around her eye? There looks like bubbles or foam in the swollen eye, and that can also be a sign of MG, but also can be do to swelling. If you think she has a respiratory infection, then get some Tylan 50 injectable, and give her 1 ml or cc orally twice a day for 5 days. If she is less than 5 pounds, give her 1/2 ml or cc. Oxytetracycline powder could also be used in her water, instead, but she would need to drink enough of it to get the medicine. Those are found at most feed stores near cattle medicines. Some Terramycin eye ointment or Neosporin can be applied inside the eye twice a day also.
I just looked again at your picture, and was wondering if she might have fowl pox from the little marks on her comb and face? That is a virus carried by mosquitoes, and sometimes the eye can become involved.
