OH SHIT ! One day , just once , it happened something weird . It was a week when I was trying really hard to have a lucid dream , and one day I fell asleep on the couch in the afternoon . I woke up for some time , then I was trying to get back to sleep . In that moment I felt like a ' WOON , WOON ' sound in my ears , accelerating , going faster and faster , and then I felt like I was bein shoot up to the ceiling , it was so fucking weird ! I was scared and happy , as if gravity had suddenly inverted , but it was really strong and sudden , like being literally shoot up to the ceiling at supersonic speed , it was like flying , but more like being thrown to the ceiling . I tried countless times to replicate this , but with no avail .