I'll be honest, I took the unrecommended attempt of WILDING at sleep time.
However I managed to stay awake, and while not moving, I guess I could feel my dream personality in my head as I felt that I was doing something although I wasn't doing anything with my physical body.
Anyway, after a while, I had my first hypnagogic imagery ever (I never succeeded at WILDing): I heard a vibration similar to binaural beats (I wasn't using any binaural beat). It didn't literally scare me, but the surprise caused my heart to jump and seemed to cancel everything.
What to do next time? Where did I go wrong?