Your Screen gets black and you can only see the sun and shadows under water with night vision potion after few minutes

I used night vision potion and water birding splash and went into the water for I think 2-3 minutes and then my screen all got black, I only could see the sun and I was able to mine or place blocks.
I could see shadow of blocks that blocking the sun or the moon.
I tried to make it happened again and I got it. i