Cats eye changed color

hello, My 6 month old blue point siamese the last 3 days one of her eyes has been turning a green/brownish color her normal eye color is blue. I noticed 3 days ago her eye was closed a bit so i thought she might have poked herself on something. Today i took her to the vet for shots and the vet said she didnt know what was wrong with her eye because it was not swollen or anything. I got a feline leukemia test and my cat came up negitive for leukemia and AIDs. The vet called me 4 hours ago and said she was reading up on cats eyes changing color and said it might be feline infectious peritonitis but doesnt know if it is because she has no way to test it. Her eye doesnt seem to bother her and my cat seems healthy running around and playing and eating. I am freaking out because i dont want my kitty to die if anyone knows anything about eye color change please help me.

Hi, I'm not a vet, but I have had experience with one of my cats developing a change in eye color (his eyes were normally green and one eye turned orange)..it required a feline opthamologist to diagnose and treat  - he had uveitis plus bleeding into the back of the eye.  I'd strongly recommend you get a referral to one.