Oh!! How I can sympathize with you on that!! On cold nights, I used to literally wear 2 pair of socks to bed, along with sweat pants and a sweat shirt, and would still have to have extra blankets on the bed! And I don't even live up north!!! I'm in Arkansas!
I'm not completely sure I can be of much help with understanding the root cause, but I would encourage you to get your hormones balanced out - thyroid, adrenal, "sex hormones" - testosterone, estrogen, progesterone and so on.
Do all you can to keep your body temp up - over dressing, drinking LOTS of hot beverages, wrapping up in blankets, use heating pads to add more warmth.
As I said above, if you aren't dealing with too much fibrin in your blood, you can still benefit from taking things like turmeric and ginger, which will help thin your blood a bit so that it's pumping through your hands and feet easier, helping to keep them warmer.
And keep moving!! Even if it's just for a nice stroll around the livingroom! Moving around will help keep your blood circulating. If you are like I was, just one trip around my small livingroom was enough sometimes, but I would get up and walk around it several times a day - as often as I could.
Here is an article about
the use of herbs to help warm the body, hopefully it will be of some use to you as well:
www.mindbodygreen.com/0-6791/5-Warming-Herbs-to-Weather-the-Winter.html