Are you sure you didn't take one of your siblings pairs?
I find mine have sort of seized up and gotten tighter. Could be because I havent worn them in a while or the cold stiffens them up a bit.
I'm the only one witha pair of falcons. I'm therefore leaning towards Robbie's explanation.
Mine are always tight when i first put them on and then by the time i'm done my course they are the right size if not a bit bigger (especially if it was a hilly long course). They are always really tight if i have left them for a while and didn't really dry them after using them.