Try taking a couple ibuprofen before bed. Sometimes we have aches and pains that are minimal if we are awake but are just enough to make a good sleep difficult.

The dreams might be a clue, though - I'm a narcoleptic so, because my REM sleep is out of whack, I can do the dreamy thing, too. While certain things that go with narcolepsy are usually triggered by strong emotions, some of us have symptoms that are triggered by certain physical motions, sudden strong exercise, etc. I can be out of a car and halfway across the street and get whacked by it, or peddling hard on the bike and have to stop because I've triggered a spell. You might want to do some Google searches and see if any of the symptoms given match anything else you've experienced. And one of the most annoying things about having it is that, although it is associated with uncontrollable sleepiness, it can cause insomnia.