When you realize you’re dreaming it’s very normal to wake up, especially for beginners. Luckily there are ways to prevent that. Once, long time ago, I wrote an article about that here on LD4all (if you’re too lazy to read the whole article, the bold words might give you a clue on what to do 
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You say that you lose your vision, it becomes black for about 10 seconds. When this happens, try to at least keep another sense in your dream. As it might be difficult for you to imagine something straight away in front of your eyes, try to keep your other senses there. You say you can move, try to grab something and from this build up your dreamworld.
Or try to remember where you were when you became lucid to make it easier for your mind to create the scene. Like you ask, think of the dream you just had to remember the scene so it’s easier to get back there.
Good luck!
Edit: you might also want to check this topic which is about “how to stay lucid”.
second edit: oh and I usually dream in first person