Dude, the main injury was to your narcissism. In that situation, law enforcement is in control, and if you challenge them, what do you think is going to happen? Let them search your car for a few minutes rather than escalate with them and be on your way.
I dunno. I see both sides.
I do work for lots of attorneys, and more than a couple have told me to NEVER let your car be searched or say anything...even if you have nothing to hide.
Of course, in the heat of the moment, and you knowing you have nothing to hide, it still would take stones to say "no" and maintain silence.
Me? I'd probably be that guy on "Cops" who tells you his life story BECAUDE I have nothing to hide!