Answer:
All of the things bothering you, such as things you are stressed about or are in your mind, busing about, come back to you in your sleep. Your body is working less so it ignores the fact that none of this goes together, so it mashes them all up to make sense in your head. Because you are busy in your day life when you are awake, your body has no time to do this. So it preforms dreams when you are asleep and not focused on something.