Couple questions: when did you notice the white spot?
Did all these symptoms appear at once (or over a short period of time)?
When did his eyes start to look swollen? Was it around the same time he stopped eating. Eyes thay are so puffy that he can barely see are definitely worrisome
Not moving, sounds like he is **extremely** lethargic.
Do you tiny bubbles coming out of his nose when under water?
Is he swimming lopsided?
Just reading what you wrote sounds like it is time to seek assistance from a vet.
RES can be sick for a very long time before showing signs of illness that we can see. Often, by the time they show symptoms they are very, very ill.
The lethargy has me most worried.
"I know up on the top you are seeing great sights, but down at the bottom we, too, should have rights"
~ "Yertle the Turtle and Other Stories" by Dr. Seuss ~