I've gotten weird temperature "surges" like that ever since I've had Lupus. In the middle of what seems like a normal afternoon, in the comfort of a 74°F (air conditioned) home, I will suddenly feel deeply frozen. I've found that if I climb into bed and turn the electric blanket up to high, I will fall VERY DEEPLY asleep and wake up in 2-3 hours with everything normal again.
The cause? My guess is some weird surge in the immune system. I don't seem to run a fever when this happens, but if I've been trying to work too hard, under too much stress, or eating poorly it's more apt to happen.
It's better than the days when my Lupus was more active -- then I would wake up in the night soaking wet and freezing. Had to change both clothes and bed clothes on too many nights to count.
If it's strange, it's probably auto-immune! lol
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2000DIAGNOSING LUPUS & HW's LUPUS 101
"Life is far too important to be taken seriously." - Oscar Wilde