The symptoms seem to indicate that you're suffering from staphitis, which is an inflammation of the eye, which can lower your vision, but it can also lead to joint pain, weakness or insensitivity in certain parts of the body, and sometimes stomach problems, and it's good to do more research to make sure that this is actually the cause of the symptoms.
Doctor, there are a few strange symptoms that are getting worse and weaker in your eyesight and weaker in your elbow, and you've got abdominal pain, and you've been biting your nails, and what's the cause of this problem?