why i had strange and bad dreams all day?

I am seeing strange nightmares every day.I m wake up midnight with fear,sweating,palpitation.I remember everything about the dream for 1or 2 min after wakeup.later it become vague and then it suddenly vanishes from my memory.at morning I can remember a little things only and sometimes nothing.

I am dreaming something like.

talking with dead people.they r attacking me,I m also try to beat them etc.some time saw world is ending.building and trees fall down ,I am escaping etc.