A Note About Shadow People

Because of my encounter this morning with the Alien and Shadow People, I decided to do some research. I don't have it in me to properly research Aliens because the experience 14 years ago and the face I saw a few years ago and the figure this morning all scare me so much that I can't sleep for days if I see make myself look at it. I turned my energy towards the Shadow People - which lead me to this article. What a great article. I like to hear what and how other people experience shadow people.
Here are my experiences:
--I hear shuffling feet in my bedroom and when I look to see what it is, it's 3 or 4 shadow people walking from my window area towards the bedroom door. They don't seem to notice me or my BF.
--When I walk into a room, I'll see figures dart behind walls, like they're hiding from me.
--At work, I'll see white shadows outside when I pass windows (good thing I don't have any windows in my office!).
--When I was 14, I started seeing black and white figures that my therapist told me were the manifestations of my good and bad energy. She prescribed me Prozac - which did nothing but worry my Mom.
--I will see a series of shadow people for a few days, weeks or months and then, I'll stop seeing them for weeks or months.
***NOTE: The last time I listened to Coast to Coast AM (1998-1999 or so), the show was about shadow people and the story they were telling was about a man who had the same experiences as me (seeing them for a period and then not seeing them for a period and then seeing them again). I got really scared and turned it off because I knew it wasn't just my imagination - that it was a real phenomenon that was happening to other people besides me. That story has always stuck with me...
But, my double whammy encounter this morning really did a number on me because when I see the "Greys" (as they are sometimes called), I don't really think anything of it and I go on about my day. But when I see Shadow People, I feel like I'm constantly being watched and like something or someone is following me.
I never feel alone regularly but after seeing Shadow People, I can definitely feel something. I don't know what it is but I can feel it.

But what does a double sighting like this mean?