First, your english is better than some people I know here, so all good.
That's quite the experience! It sounds like while you were down there in the darkness you opened your mind to the non-physical a bit and that's what you heard. It was more likely a voice from within which was a reflection of your fear of the darkness.
I'd suggest just sitting down there and exploring that a bit and see what happens. Just know that you are perfectly safe and nothing is going to harm you from the non-physical.
That's quite the experience! It sounds like while you were down there in the darkness you opened your mind to the non-physical a bit and that's what you heard. It was more likely a voice from within which was a reflection of your fear of the darkness.
I'd suggest just sitting down there and exploring that a bit and see what happens. Just know that you are perfectly safe and nothing is going to harm you from the non-physical.