Had the same problem. Except I was in full Gorka gear. Inside, next to a fire. Died without being able to do anything about it. I had a thermometer on me and could slowly see my temperature fall to 34 degrees celcius. We were cooking 10 steaks as we noticed it.
Edit: I forgot to mention, some of my clothing items were soaked from me filling a bottle earlier. I replaced the soaked items with spare, dry clothes I was keeping for a buddy. There was a storm outside at the time. Sky was pitch black and it was pouring rain. The building we were in was a two-floored green and white building with the blood-stained piano inside it.