Those blood cells you can see when you look at the sky--are those in the lens of your eye, or the retina, or where?

Just a moment ago I was staring off into space, and I saw my blood cells (some people won’t understand what I mean—not everyone recognizes it). Strangely, the cells were glowing bright gold, rather than being transparent as usual. I thought I was having a stroke or something. But I turned my head slightly, and they went away. I notice that my bedroom lamp is in a good spot relative to my head for refracting into the lens of my left eye, and the lamp is the same color, so I’m going to guess they were being illuminated by that refracted light.

It made me wonder where, exactly, those blood cells are when we can see them. I’m guessing not the lens, but where then? I only ever see one or two at a time, never a constant stream of them as I would expect. What part of the eye can function with so few blood cells going to it?