With these types of posts, I tend to go with gut instinct and certain keywords to see how "real" they are. I can usually always tell. With yours,
I think it's real, only because of a few things you said.
You said "they" came in three. I have had my fair share of experiences and in my experience, they always come in 3s. Three is sacred to them in
some way: they always come in 3s, I always know when they're coming because it's like seeing number codes of 3s, I associate them with the triangle
with circles over the tips (all 3s), etc. Some times I would hear a strange knocking sound in my walls and ceilings, knocking in 3s, that seemed to
come from the walls and air at the same time.
You mentioned the sound. Only twice have I experienced the sound, but it is the most surreal sound I have ever heard in my life. The humming &
buzzing is both very low, like the lowest frequency sound, almost a rumble, paired with a very, very high-pitched whirring sound, simultaneously. For
me, it was both painful and acted as an instant, strong sleeping pill. It literally is immobilizing. You just don't hear this sound, you feel it,
in every inch of your body. It is like it induces sleep or fainting or something. Whatever it is, it works.
You mention the bright light. May I ask, was it bright but soft bluish-purple as well? Or perhaps bright blue, electric blue, like on electronic
buttons? I've seen both kinds. The first beckons, is gentle. I have woken up to my bedroom filled with that color, thinking it was dawn or a full
moon in my window, walked to the window and looked out realizing there wasn't a moon and looked at the clock, realizing dawn was hours away and
strangely, got back in bed. I have only dreamt of the second kind. It is harsh and almost alive in its own right, intelligent I guess. The second
kind of light was what I once dreamt was chasing me. I hid behind furniture and it sought me out, lifted up the furniture until it was floating in
the air, then got to me. When it got to me, however, it didn't hurt, but my skin had the strangest tingle and my arm disappeared, yet I could still
move my fingers, I could just feel them moving somewhere else, it was like the light acted as some sort of matter "re-organizer".
I know some will say that this didn't happen or it was a dream, etc., but these things do happen to people