What does a dream of a shadowed figure that is not you mean?

I had a dream that it was a normal day and I was older and me and some friends were just having fun while were in this country area. Well, there is this black shadowy figure that is watching me. I know its just me, I have this feeling that it is just me. It follows me everywhere like a shadow but its not my shadow because I have this feeling that it is a man. I've actually had dreams with him in them for quite some time. The shadow man never makes any contact he just watches. I just wanted to know what it meant. A friend of mine said that there are people who can channel into your dreams and that you have to be careful. I just wanted to some outside advice because this used to happen when I was in middle school but now its happening again and I've graduated from school.