Although I can't give you a full interpretation, I don't believe in meanings in dreams or anything like that, I can relate to you. I have a fear of deep water/the ocean and I've dreamt of being stranded out to sea a couple times in the past. Everytime I've woken up I've been pretty shaken, couldn't stop thinking about the dream for a while. I don't think it's uncommon to dream about a fear. So talking from experience, I can see how you feel and I can tell you that after a while it will just pass, you'll stop thinking/worrying about it.

Sorry if I wasn't too helpful but at least you know you're not alone!