Since you were lucid and tried to rule out other possible causes, I doubt it was a hallucination, but then we don't understand consciousness very well, so maybe it was. But I doubt it.
I like it much better when people show themselves the way we typically think nonphysical people look like: white, transluscent figures that float along. I have seen only three like this. One walked right past me like it's cool, ignoring me. I've seen hundreds it seems that are dark, shadowy shapes. A couple have been glittering flashes of tiny lights. They sometimes do rather rude (the American sense of rude, which is VERY rude) obnoxious things to get my attention. A favorite tactic for some of them, especially when they are new, is to make really loud noises, draw me out, and then move in front of me so I walk through their energy, which I REALLY don't like. This is when I don't sense them first. If I sense them and look in their direction and aknowledge their presence, even saying something to them, then they don't bother me like that, although they are *always* there. I'm always being *watched*.
But I am one of those people who attracts them. Usually they are recently passed, are scared, and want me to help them. They are just people, after all. Some of them are children. Most are quite shy and some even hide, believe it or not. A couple of weeks ago I was at my ex's house, sitting on a sofa, and a child kept peeking around the wall of a doorway, checking me out like children do when they are shy. They seem to know I can see or otherwise sense them.
Nothing to worry about, really. Just life.
I would let go of that fear though. They can read your thoughts. The last thing I would do is even think about hostility towards them. If you were in their position, would you be direct about getting your attention, or would you do something else? I'll bet whoever played that little trick on you was afraid to approach you more directly or knew it wouldn't work anyway, so they did something spooky.
My *friends* don't do spooky things to get my attention. Obnoxious things, rude things, yes, but not *spooky* things.
They can play with electrical things, lights, move objects, depending on how powerful they are and what the conditions are. I've got one right now who hangs outside my front door, staring through the window, watching me constantly. This one tried doing the thing with the lights outside the door but I didn't come out this time. So (he) just watches me through the window. I actually feel sorry for them. I do retrievals in my sleep but I don't do them awake, so there is little I can do for them, other than talk to them. Sometimes I can hear them, but usually not. Sometimes I project Love to them, but that's all I can do.
One thing they NEVER do is violate my personal space. I mean they don't do obnoxious things in my inside my flat. I don't sense them in there, either. I don't know why, unless it's because my guides are keeping them out. Outside my flat, anything goes.
They even follow me. I'm surprised you saw what you did inside your personal space. I would ask your guides to let you know who that was and then pay attention for the answer.
It's interesting to know that whatever house I walk into becomes haunted as soon as I step into it!
Another interesting aspect is I attract them with my energy, and they can read my thoughts, so I must not be too bad a guy, right? Anyway, some of them are women. So, I have more dead girlfriends than live ones! If the live ones could see what the dead ones see, I would have women all over me
. Oh yeah, one of my guides is a former spouse, and a member of my disc hangs around too, another female. So while the dead ones follow me around everywhere I go, the live ones are blowing me off! Life is sooo unfair! Well, the live ones aren't really blowing me off at all, but sometimes it seems that way, you know how it is.
I hope all this helps reduce your fear somewhat. Start paying more attention to what is going on around you. You might see more than you expected. And let go of that fear! If that someone wanted to hurt you, you would have known it by now.
Bob