Dreaming that i'm helpless?

For the last week, I have had a reoccurring dream about being alone on a deep sea submarine that has broken down. Each time I have the dream, I get a little further. There's an initial panic, and I obviously try to fix the problem. But after that, there's just an empty and hopeless feeling. And I kind of just sit there by the large porthole and watch the bioluminescent sea creatures float past. It's weird, but it honestly feels real. I don't know, it's just not something I'd normally dream about.