My girl got a cut on her eye rough housing with her cage mates it’s been only a scratch until tonight I noticed it’s completely swollen and white. I’m terrified of having to put her down and would just like some feed back
I am not an expert at all but my first instinct would be to go to a vet. They will probably give her either eye droplets and/or antibiotics to help. It sounds like her wound got infected with some nasty bacteria.
It sounds like her eyeball got scratched or punctured. At this point you need to watch to see if the eye either starts bulging out of the head (can't close eye fully) or shrinks and changes shape. The latter is a punctured eyeball where the fluid drains out slowly, the eye shrinks up to a nub in the eye socket. For scenario 2 you just need to prevent infection and your rat should be fine. In the first case you will need a vet visit ASAP.