hello there i am not an experienced one but i can tell you some facts related to your question.
1. i think that was a lucid dream with a good level lucidity.
2. when you were bouncing and trying to imagine hard that you should stop bouncing at that time you internally knew that you may not stop and your thinking may not work .suppose if we are passing through a wall in a dream and we try hard to imagine that we will pass through it but we have different experience with walls in waking life which creates a mental block and we could not pass it right away but if we realize the full implications of dream then we will definitely pass through it. so next time you are in a dream just stabilize the dream and think about some memory of waking life that will help you increase your awareness and things will be easier for you.
3. do not close your eyes in dreams ever it may collapse your dream.
4. do not use negative words in dreams our subconscious mind don't accept it so when you thought don't make a shark appear your mind took it as make a shark appear and left don't.

and congratulations you had a 30 min long dream i am struggling to reach that far.