Seeing Shadows And Spirits

I was about 4 when all of this started. I could kind of see what was going to happen right before it happened and I was (and I still am) able to describe places with great detail that I've never been to in my life. Like once I was getting ready to go to my friend's house to play (I was about 8) and I took a nap before we had to leave and in my dream we were in a room with purple walls with fake butterflies hanging everywhere, tan carpet, dolls everywhere, and a few other toys scattered around. When I woke up, we left and when we got there that was exactly what her bedroom looked like. I have never been in there. There were some shadows that looked like people that were moving around a little bit, I felt a mix of emotions inside me, half was anger half was fear and a little bit of it was happiness. When we got home I had to go to sleep. And while I was in bed, I saw those same shadows and I got the same mixed emotion feeling that I had earlier. Those creepy things followed me. I finally fell asleep, and in that dream I was back in my friends room, there were more shadows there, more than before. They were all talking but I couldn't really understand it was kind of all gibberish, more like moans, and I'm 13 now and the same thing still happens. Except there is only one shadow that visits me now, he isn't even a shadow, he's my great grandfather that passed when I was 4. And 4 is when I started with these odd abilities, seeing places, spirits, crazy emotions, controlling spirits, and my great grandfather. I am pretty terrified at what is happening and I think I might be a medium. I don't know! I will do more research. I don't know exactly what is happening to me! Help!