I'd definately second Lara.

If you have anxiety, depression or feelings of guilt this will manifest in your dreams. It's your subconscious dealing with it. This is not necessarily PTSD, that also comes with sensory recall and is often specific and repetititve.

Lucid dreaming can seem to overlap, in that you are aware of your body, as you are aware of the dream. If you cling to the dream and but try to move your sleeping body you will compound the feeling of being trapped. Accept that your body is resting and seek to move the dream instead.

Its actaually really fun. If you're already anxious then you need to prime yourself. Read a favourite book and pull the dream into that world. Or your version of it rather.