But YOU!
you are the only one who can interpret what the dream is about. It depends on what the symbols in the dream mean to you. One can generalize to a vague degree, such as "dark water means the unknown" which would probably be true for many. The answer is dependant on your own experience. The question to ask is "what in my life and current frame of mind would 'unable to move at normal speed" symbolize?
Based on the fact that you post here at DU might suggest that you have been waiting for a change in the political direction of our country for too many long years now. Your presence here might be telling of how strongly you feel about what has happened and that we've all had to get through this agonizing wait in the election cycle. That wait seems to become more intense in these last days for me.
The previous posters comment about how the brain governs the body during sleep might be relevant too. Ever woke yourself up kicking or punching at something with all your might in a dream, only to wake realizing your limb has barely moved a couple of inches?
What else are you waiting for in your life? what is it that you are not able to get to right now?
Figuring out what those symbols mean to you, will lead you to whatever your subconcious is trying to tell you or simply reflect from your waking mind.
Gee, I should work on the bad one I had the other night about groups of somnambulitory groups of people being "herded" around a football field in the middle of the night by small, bright blue creatures with giant heads while silent "things" glided around overhead.
Brrr...