Afraid I'll be trapped in a nightmare?

Poor you! That sounds scary! its weird cos though it was a dream, it sounds like something I have experienced that's called 'derealisation' where the world seems to turn 'fake', 'changed' or 'strange'. There are websites about that. but cos yours is a dream, all I can think is that your mind is worried about it, and that triggers another dream. I know it's terrifying but just remember dreams cannot hurt you. I have heard of people who can alter what happens in their dreams by mind control too, like one who changed the end of his recurring nightmare. It also sounds a bit like a condition called 'sleep paralysis' where your mind is awake but your body isnt, so you dream about being trapped, or forced into danger, cos your mind is going oh my god wake up body!