@Nessa7 All of my dreams are fictional, in general, but use elements of my history, such as places I lived. Often, the elements of my history are cloaked in ways that obfuscate what they actually are. I had a dream, last night, that involved a house... after thinking through it, I realized that the house was nearly the same model as my childhood home, but decorated differently. My therapist told me that this is a protection mechanism -- your mind reveals things very slowly and carefully, in order to prevent being overwhelmed by whatever horrible stuff lurks beneath.
I don't feel a lot of outright fear in my dreams, but there is often a lot of anxiety, which carries through into the day. Also, the mood of the dreams is often dark and dire -- you mentioned a feeling that the "world is ending", something like that. And, occasionally, my dreams do cause fear. I know I wake up a lot in the middle of the night, even if not fully. Sleep is a big problem for me.
When the dreams first started, I didn't have much emotion from them other than that dark feeling. Gradually, however, they've become more vivid and more realistic. And, lately, they've started focusing on more concrete topics instead of symbols. I of two minds about this -- yes, I want to learn more about my past, but I'm also scared as hell as what I'm likely to find.