Dreams are regarded as a path that tilt between our physical world to the spiritual realm. Some people have the gift of dreaming and it's interpretation while others just have their subconscious play with them with silly dreams.
Yeah, that happens to me too. If I was doing something during the day, usually I dream with something related with that, just with a strange twist like if I am flying or so.
Its really hard. Sometimes I dream with my late dad and grandmother, those dreams are dire to me because that's how I can really feel them and know they are there with me by my side. Sometimes i have bad dreams, probably am getting shot at and those dreams I never wanna relate.