Nothing wrong with being paranoid. Rabbitfish are just weird sometimes. My current gold spot sometimes darkens in color for days at a time. She will still eat like a pig, but goes very secretive and hides outside of feedings. Then randomly she will be active and swim for days at a time, then back to the hiding!Dipped. No visible signs of parasites. Going to watch for any signs of infection or similar issues. I think I’m just paranoid.
I recently put in a new bicolor foxface, so she's interested in following the little guy around as of late (she was sharing the tank with a Foxface Lo previously).
Im leaning towards the usual weirdness in your case @ this point! If it was flukes, watch for the feeding instinct, they wont eat if blind. I went through it a few months ago, poor gold spot was almost blind and the Foxface Lo went blind and died before I realized it was flukes...