Am I seeing what I think I am?

I believe I can see people who are no longer living. I'm not concentrating when it happens either I am thinking of something completely different. I know I could be imagining or over thinking it but I sometimes think it's not that. The first thing I saw was someone familiar from my childhood. When I was younger I had an imaginary friend and I never saw him I could only hear him....he talked to me never told me to bad things just talked to me. His name was John....I only saw him once or twice in a dream. He was tall had dark brown hair and bright blue eyes. He was wearing a tuxedo. Because of my age I thought he was getting married. I wasn't scared of him he was my friend. As I got older he disappeared and I matured. Around the beginning of winter when snow was already on the ground, I saw him. He wasn't looking at me he was facing the obvious opening opening near my neighbors house. The sun was shinning on him and everything in his path. My memory is quite blurry but I rememeber I saw him. I have always been afraid of spirits good or bad because I've watched Paranormal Activity all of them except one. I know it's not real but it gives me that scared effect even after the movie is done and when I go to bed. I found myself scared so I walked faster to my house hoping I wouldn't see anything like it again. I'm fourteen and I am with my sister who is pregnant and is a senior she sometimes walks with me to the bus every other day but sometimes she doesn't come at all because of appointments or meetings. The next person I saw was another man. I was walking alone to the bus unlike the first time where I was walking home. I live in a trailer park and I live the furthest away from the bus stop then the other people who take the bus so I start walking around 6:40AM so it was pretty dark. I was walking past my friends uncles house and he has this red or orange truck I can't remember. And out of the corner of my eye I see a man he is looking at me from what I can tell. He has a gas mask on it had something in it it was white but red maybe from dirt or something I don't want to say it was blood because I don't know what it was. All of these things I have seen quite clearly out if the corner of my eye. I of corse got scared and started to walk faster to the end. Those two times were closer together but recently I've seen one more thing. Last night I was in the shower and I was stroking my hair to get the conditioner out. My arms were behind me and I was not moving anything except my arms which again were behind my head. I was looking around the familiar area of the shower (I was facing away from the faucet) and out of the corner of my eye I saw a black shadow like circle move shortly towards me then it disappeared. I wiped the water from my face and looked again. Nothing. The shower curtain didn't move because I never saw it move. I don't know if I'm going crazy or if I'm seeing things that aren't there. I don't know what I'm seeing or what I've seen frankly it's scaring me. I think I'm going crazy. Does anyone have any answers for me? Advice? Anything?