Does anyone have spurts of excessively vivid and scary dreams?

I have been having them again lately--so real, gross and terrifying. I sometimes have them for long periods of time and then I go through phases of not remembering anything. I usually--99% of the time will not remember a dream unless it is soooo scary and real. I am going through this phase again and having a normal dream totally shocks me. I don't know how to stop these nightmares. I can even feel myself being stabbed and shot sometimes. I recently had one about an friend falling from a rollercoaster and being eaten by an alligator in front of me and others. I see horrible things. I think I could write a horror film. Do you ever have this problem? And no--I don't drink or do drugs. Thanks for your help.