that sounds awful. I haven't felt that kind of thing in a long long time so I'm not sure I remember details but I know it was bad. I remember the first time I felt extreme anxiety at bedtime as an adult. Like your night, there were no warning signs or identifiable causes for me. I closed my eyes and thought all was well when my eyelids went up like a cartoon character's windowshade eyelids and the fear was there almost instantly.
Back to the ghosty/monstery thing...I believe I got past that when I began to love the night and the dark. That happened long before I was your age.
I can't tell you why it's happening tonight but I'd say go ahead and leave a light on if it helps.
It's too bad you can imagine the ghosts but you can't imagine someone there to comfort you. Doesn't seem fair does it
I read your post earlier about blocking people. I hope I'm not typing this for nothing