A Shadow in Sunny September

It was a sunny September afternoon in 2014, I was laying on my bed watching YouTube videos when something caught my eye. I glanced to look and there was a shadow, I blinked a couple of times to make sure it wasn't my eyes playing tricks on me but the shadow wouldn't go away. As I was staring at it, I realized this was no ordinary shadow. It wasn't blending into anything like a shadow would, it was standing up, with a 360 degree feel about it; come to think about it, it kinda looked like a person with a black robe on, it also had a smokey texture to it. I was in awe, I just couldn't keep my eyes off of it. As I kept looking, it began to move, I could see it turn towards my bedroom door and almost walk towards it. I kept looking, almost frozen to the point I couldn't do anything else, then as quickly as it happened, it walked through my bedroom door and out of my room, this experience seemed to last forever, almost as if time stood still, or at least time had been halved so everything was in slow motion. Once I realized what had happened, I swiftly got up and went downstairs to be with my family, they could tell something was up because I was "as white as a ghost" as they explained. I pretended nothing had happened because where I live, no one believes in the paranormal. Once the whole situation calmed down I started to do research on what this shadow figure could have been, and the most striking theory was that a shadow figure could be someone having an out of body experience, or perhaps a sign of death. I didn't believe in it really.. A month before this happened, my great-grandmother passed away, but the most striking part of this whole story? 3 months after seeing this shadow figure, my grandfather passed away suddenly with no warning. Coincidence? I just don't know!