Realizing something is a dream but not being to wake up?

[dinofs]

Mainly in nightmares, I have realized I am dreaming. I will attempt to wake up, and either I will think I have and keep going, or I will become upset and start crying.
Why is this?
Sometimes, this will happen multiple times in the same dream.

[PinkMellow]

When I was little and couldn't wake myself up, I would close my eyes, and that would make me open my eyes in real life. You can try that. I'm not really sure how I gained my ability to wake myself up after closing my eyes didn't work anymore...it's kind of like I tell myself "I'm done with this dream!" and then I wake up. Much like if you're thinking about something you don't want to you're like "Ok changing topic!" In addition, you can change the whole atmosphere of a dream by injecting humor into it....just act really silly. Makes things more fun.