Temporary “curtain-like” vision in one eye when bending — should I worry?

Hi, I’m 23F and something weird happened today (and it has happened twice before months ago).

I was taking a bath and bent down to wash my hair, and suddenly in my left eye only I got this black, curtain-like partial vision — not complete blindness, but like part of my vision was blocked/dark. I could still see a bit, like thread-like structures.

It lasted around 2-3 minutes, then gradually went back to normal. After that I felt quite dizzy, like my head shifted, but didn’t faint.

Some context:

- It only happens when I bend down

- I hadn’t eaten for a couple of hours before it

- I was in a hot shower

- My BP is normal (115/70)

- Blood tests are mostly normal (slightly low vitamin D, borderline B12/iron)

- No headache, no flashes of light

It’s happened twice before in the past few months, same pattern.

Would really appreciate any insight!