While nightmares are common, nightmare disorder manifests as nightmares so vivid and so frequent that they create major distress and daytime impairment. These nightmares routinely disrupt sleep patterns and typically occur in the earliest hours of the morning.
Although I had vivid dreams in my formative years, they didn't amalgamate with terrifying flashbacks until I developed PTSD. Over the years, the vivid dreams bled into restless nights, hellscape nightmares, night sweats, terrifying sleep paralysis, and the eerie sensation that something was sitting on my chest. On the worst of nights, I was certain that I'd suffocate.
What do you see in nightmares?
My sense is that people expect to hear about specific themes: direct trauma, phobias, or readily apparent anxieties. They rarely are that way. What I feel and see, I really feel and see. It's just not of this world.