no, sometimes we remember our dreams and that re-implants them and other times an external trigger brings back the same memories. i dreamed a real good movie once for two weeks,but forgot to write it down. could have been a millionaire.lol.
It's odd that you've actually kept track well enough to know the time between dreams. I don't know of any real studies about repetitive dreams--I'm sure if you Google it the studies will most likely be numerous. I have had 1 dream that for some reason pops up every now & then from when I was a small boy. There's no telling when it'll occur, but it does.
Not unusual. It is possible around that time something big happened in your life and that is why you are having that dream. Every summer I had the same dream since I was 11. I was being chased around my yard by 2 clowns in a jeep, I would hide but then they would find me and I would have to run again. One day about 15 years later it just stopped, but I am still not that crazy about clowns. lol
I have a friend that has had the same dream for the past 7 years, its of a girl dying but he can never see her face. I think its a subconscious thing, where something bothers you in the real world, and then it interprets out in your dreams. It's obviously something you can't let go of since youve been having it for 5 years, and its probably the smallest thing that you never noticed. I think the reason my friend kept having the same dream about the girl was because he was never good at relationships he could never be there for whoever she was, because he was fighting his own demons, called bipolar. I think the girl died in his dream everytime because he was so used to losing people, and there wasnt anything he could do about it. Look up whatever dream your having online and see what it relates to.
It's not unusual. Dreams are in the subconscious mind and while they may not make sense to us is because our conscious mind is analyzing them but its not the dream its the symbols of things they might represent that need to be looked at. Dreams or nightmares are situations that have happened or things on our mind whether good or bad and are effecting us. You could dream of someone chasing you and be fearful when really your subconscious mind is seeing the person chasing you not scary but something your not dealing with and running away from, the scary person symbolizing something else. Fact it has been a time gab between the dream maybe try look at why, what was happening around you when you first had the dream, what is similar happening now? There will be a pattern something unresolved for you to deal with and put this dream at end.