Well, there are many theories about where dreams come from. There's Freud, who says that all your dreams are about sex and that they are full of penises even if they are not. Then there are those who believe that there's an actual dream world (astral plane) where you go when you sleep and that it's as real as this world, only more subsceptible to your intentions. There are others who say that your dreams try to work out what you've been doing all day and to connect it to prior knowledge. Then there are those who think that dreams are just random shit people just think too much about because they think that because a dream seems very real, there must be something to it.
In the end, as usual, you have to make up your own mind.
But you may want to sleep about it before you make a decision.
