I had the same problem on my 07. No noticable fluid loss but def leak at the thermostat. Took it into my dealer, no questions asked. They didn't even check the computer to see if my 3 year warranty was legit (they know me pretty well since I'm in there looking/buying something every two weeks hehe).
They ended up flushing the system, changing the thermostat and replacing the O ring. Still some good shops out there.
Falling down is your bodies way of saying you just screwed up.