The first time I attempted the MC, I ended up quitting because of the cold. It was ill advised to start in December, but we did anyway. Three days later, I was sitting on my couch in a fully heated apartment wearing every piece of winter gear I owned and covered in blankets, shivering, thinking : This Is Ridiculous. It kinda was. :) Anyway, I think it's just part and parcel. I know that more cayanne is supposed to 'warm your blood' but it doesn't seem to make much of a difference to me. I'd say just bundle up.
Day 15? How long are you shooting for?