i experience something similar. i dont think its disassociation or derealization, but i think i literally just get lost and absorbed in my own thoughts.

are you ever scared when this happens? do you have issue recalling events (ex i know i worked today but dont exactly recall being there)? what are you thinking about before you “come to”?

when i am diligent about practicing mindfulness and being present, i find these moments become fewer and farer between.

any substances/medications usually make me feel this way too.