I recently received an email from someone who has been doing this sadhana for a long time and I thought you could benefit from reading her experience of pratyahara:
The first experience I had with Pratyahara happened very suddenly. There was no perception of anything, and as if in a dream I tried to communicate to someone/something out side myself, and there was nothing working! At first I kind of freaked out and then I recalled reading about Pratyahara and wondered during the experience if that was what was happening. Then when I relaxed and “let it be” there was a sense of purity of silence, stillness, nothing needing to happen. I was just with myself.
One thing that I wanted you to notice is that she “kind of freaked out”. This is one of those magical moments that some people miss and stop their sadhana because they become frightened.
Also notice what she did about this. She remembered about pratyahara, which means that she had foreknowledge of it. This is where I get to preach about learning, both through oral teachings of the lineage and through the study of scripture. These two will save the day in situations like this, just as it did for her.
Keep in mind that change is inherent in progress, and change is always a little spooky because it is not familiar. To the less fortunate, this spells danger. This sadhana requires at least a little bit of the spirit of adventure. It’s what makes it so much fun!