I rarely have nightmares, but when I do it's normally connected to something that's going on in my life that's effecting me negatively, no matter how small an effect it's having.
I have two nightmares that I can remember clearly despite having them when I was between the age of 13-15, and they're ones I've had several times, during several consecutive days.
The first one was about how somehow my sister who was living with us at the time had turned into a zombie, she'd already killed my dad and my brother so it was just me and my mom, we'd managed to get to my bedroom and lock the door.
I remember thinking in the dream-world that we'd be okay now, she'd go away once she got bored -or hungry, whichever- and then we'd make our escape. And as soon as I'd finish that thought, she'd jump out of my wardrobe (which I could never understand as she was locked outside the room) at us, biting my mom.
That's when I'd wake up sweating.
At the time of these nightmares my sister -the none zombiefied version- had been living with us, and everyday there had been some sort of argument with her at the center of it, causing a lot of tension in the household -I guess my subconcious had somehow twisted the effects it was having on me so I wasn't ever really away from the stress of it.
The second nightmare was when I was really depressed and hadn't been out in 2-3 months, and had hardly left my bedroom.
I'd wake up in the dream-world -which is so weird by the way- but I'd be stuck in the same position; on my back with me facing my wardrobe, at first I wouldn't think anything of it, I'd just groggily glare at the wardrobe, but then I'd start to feel this ominous feeling, like something was there, in front of the wardrobe, something watching me.
I'd start to panic, trying to pull myself out of bed but to no avail -and that's when this thing would strike.
I can't really remember much about what it was, just that it wasn't a solid figure -maybe an apparition/ghost. But I do remember it launching itself at me so we were face to face, it's face a mere inch or two away from mine, and silently screaming at me, and that it resembled that of an old women, her wrinkles being prominent.
That's normally when I'd jump out of my sleep half way through a panic attack.
I guess my subconcious was sick and tired of me staying in my bedroom that it decided to scare me to go out -which it worked after several days of the same nightmare plaguing me.
It's rather interesting how you're subconcious can be utterly cruel at one point, then, though slightly twisted in the way it done it, rather kind.
...
Or it could just be my messed up subconcious.
*Shrugs*