Function over Form

Ladies, sometimes you just have to put function first. An avowed non-fan of UGGs, I never thought I'd see the day when I'd break down and buy a pair. And yet, that day has arrived; today, in fact. To clarify:  I didn't actually purchase boots under the UGG label (they are astronomically expensive here). However, I did buy a pair from a competitor which look awfully similar. Yes, I realize I signed up for insta-cankles, but too many days in succession of having no feeling in my toes pushed me over the edge.

I'm now wearing said boots in my apartment, and my toes are enjoying some rather toasty warmth. I'm also wondering if it's possible that only three hours ago my feet were a 1/2 size smaller. When I tried on the boots at the store, they seemed to fit fine. And now, after my toes have warmed up, they feel a little too close to the boots' tips. Hmmmm... anybody have any insight? Could my feet have been smaller earlier today due to prolonged time outdoors in the extreme cold? Is it possible to stretch these boots now that I own them? Any idea on how to go about exchanging goods in a country where you don't speak the language?!