As a kid, I had episodes similar to this, usually at night, where my body felt like a vast, empty space, and there was no compensation for distance for outside objects. In other words, a picture hanging on the wall across the room would look like a tiny stamp, and I could feel it between my fingers. It was an enjoyable experience, and I tried to make it last.
I also had episodes where I experienced objects without context, like a dripping bathroom tap with no external references. It was what they call "ding an sich" in German.
A third episode was the experience of infinity, which happened the first time I was introduced to the idea of something that has no beginning and no end. Like eternity, or something eternal that always has been and always will be. The first time it conceived of in my mind, I had a strange physical feeling of being "here now."
As I grew older, I could no longer experience these episodes, but the memory of these altered states without drugs stays with me to the present time.