yeah dude you had an accidental WILD- the sensations you experienced prior to the dream are known as "Hypnagogic Hallucinations" - you basically experienced your body falling asleep. Happens every night most people loose consciousness by then though. Lucid dreamers use this method to have lucid dreams - seems you've had your first taste

Hypnagogyc Hallucinations:
http://www.dreamviews.com/community/...ad.php?t=65425

WILD:
http://www.dreamviews.com/community/...ad.php?t=66238