I think this is AIWS

Sorry for the long post. I've copied what I wrote to chat GPT hoping to finally find someone with a similar experience and it's been really interesting reading other people's experiences having been alone with this for 34 years. I'd asked friends and family and even a therapist about what happens but I'd never found anyone with any knowledge of it, so it's nice to know I'm not alone. Heres what I sent to chat GPT for it to direct me here:

So it happens when I'm in a relaxed state, usually in bed but sometimes when I'm sitting up playing the playstation or something that takes little brain engagement, reading a book maybe. Usually when I'm tired. It doesn't happen very often, like once a month but often it won't happen for months at a time, possibly even years have passed between it happening. It's happened as long as I can remember. I'm a 34 year old man for reference. How it plays out is I'll be in bed, maybe reading or just lying thinking, trying to fall asleep, and it comes on slowly. It's a strange combination of lots of things, no one thing being more over riding than another so I'll try to describe them all. I think initially I'll be aware of feeling enormous, like I am a very large entity taking up a lot of space or conversely I am a very tiny entity in a vest expanse of space. Like I am aware of the room I am in but also that there is an eternity of empty space there. Then I will become hyper aware of any sounds, like the rustling of bedsheets or the turning of a page will be in very sharp relief but also like they are part of a predetermined soundscape, like they fit into a song, when the pages scrape together part of my brain goes "yep that sounds fits in the right place, I was meant to do that." In the background of this is a feeling of building dread, all the sounds are screaming at me that something bad is going to happen. It feels like it's all building to a crescendo. If there are no sounds then the silence feels very loud and is also building to something. This all probably sounds like a panic attack but my heart rate is perfectly still or low even. I can sit with these sensations and observe them and try to understand what is happening for a while, maybe 5 to 10 minutes, though eventually I will want it to stop. I think I have experienced making it stop by just trying to be very aware of it and making mental notes of how I'm feeling so I can describe it but most often how I get it to stop is by watching a video or maybe listening to a podcast or audio book which will usually snap me out of it pretty quickly. I have a vague memory of when I was much younger that these sensations would be accompanied by a feeling like my limbs were fat and round and formless like giant tic tacs but that doesn't happen any more and is just a memory.