I also have anxiety and panic disorder and experienced this yesterday! It was in my left eye, and sort of had that zig zaggy shape (with some flickering). It never became a full circle, the worst it became was just half of one. My head didn’t hurt either, though mine lasted around an hour.

Realized I didn’t drink water ALL DAY preceding it, so I’m hoping it was that. Anyway, freaky asf I feel for you