Sam has feelings for Ruby way before she lets him know that she has them for him.
This video sucks I know, but enjoy ...
Song used = ACDC Whole Lotta Rosie (for some reason it sounds like Ruby to me lol)
San Diego Comic Con, 2009. With Misha Collins, Jim Beaver, creator/executive producer Eric Kripke, and executive producers Ben Edlund and Sera Gamble. May contain spoilers!