From what you wrote, it doesn't sound as though these dreams really qualify as nightmares.

However here are links to 5 articles, from PsychCentral's archives, that may be of some help with regard to figuring out what these dreams are all about; 3 on the subject of nightmares plus 2 on the subject of dream interpretation in general:
More Than a Dream: The Science Behind Nightmares | Change Your Mind, Change Your Life
How to Eliminate Recurring Nightmares
The meaning of your nightmares | Unleash Your Creativity
How to Analyze Your Dreams (And Why It's Important)
Interpret Your Own Dreams - Some Guidelines | Healing Together for Couples