Is seeing faces and shadow people/creatures something I should be concerned about?

Is seeing faces and shadow people/creatures something I should be concerned about?

I’ve always seen things that weren’t there. I always understood they were not real but it didn’t stop me from feeling scared. I see things while wide awake. Sometimes they disappear, sometimes they stay even after I stare at it directly. Professionals never took me seriously, like I was making it up for attention. I assumed no one else experiences this and it was something I was making up in my head. Is seeing things a cause for concern if I’m fully aware they are not real?