(not) warming up

I've mentioned before that I'm an endothermic sort of person and that I have an especially hard time keeping extremities warm. I'm usually ok outside (except for my feet) when it's cold because I wear lots of warm layers.

The problem is when I come in out of the cold for more than a couple of minutes, i.e. for lunch. For some reason I'm fine when I first get outside, and I can stay outside all day without feeling unbearably cold. This is especially true if I've spent the day running around. But once I go inside and start unravelling layers, my body seems to think, "ok, now we're done with that cold stuff" and it is impossible for me to warm up when I get all dressed up again and go back outside.

This is especially true at night. When I get back to my hotel room, I always start a nice long, hot shower, and find that I can't bear to turn off the water because I'm so cold. If we go out to dinner after fieldwork, I also tend to start shivering uncontrollably/need to wear my layers during and after dinner.

I know that eating tends to make me cold because all that energy is going toward digestion (and in the field I eat a prodigious amount of food). But I'm not sure why going inside and then outside fouls up my system so much.