Swelling around eye in American Toad possible malnutrition PLEASE HELP!

[Alaina]

I have had an American Toad Female for 10 years. Recently I noticed swelling in the membrane of one of her eyes. She still eats and poops normally. It rapidly got worse and the first layer of skin is now torn and there is a very small amount of blood. I have not been taking very good care of her sense I started college. I know I have not been feeding her enough variety of enough food. I was very busy recently and kept forgetting to feed her. I fear this my be the cause of the problem. I read online that Vitamin A deficiency can cause swelling around the eyes. Also from my reading I fear she my show other signs of malnutrition. I have never dusted her food with supplements I did not realize it was important for amphibians ( A stupid mistake that I regret I have turtles and have always given them supplements). I plan to start but I am unsure about the dosage. I also do not know enough to know how series her condition is (but I fear it could be very bad). I will try to post pictures below. In spite of my recent negligence I LOVE this toad she was my first pet. I am DEVASTATED that I have neglected her and caused her to suffer. I also fear I may have been giving her a substandard diet for along time without realizing it. PLEASE HELP. I worry that it I do not fix what is wrong soon it my be to late.
Some additional information. She is housed in a 3ft by 1ft terrarium with soil, live wheat grass and a tunnel hide. She has a filtered swimming pool that I change the water in regularly. But recently the water has been dirtier than usual as I was having problems with the filter (that is now fixed). I caught her in the wild when she was about fingernail size I decided to keep her because she was missing a back leg and I feared she would be a easy target for predators. So the missing leg in the pics is not something new. I am having trouble uploading pictures but will keep trying.


Here is a link to an imgur album with more pictures: http://imgur.com/a/nwhEC