Hi hsiw and all,
This is a topic that I'm familiar with and I know I have'nt gone into my background problems on here yet, lengthy and involved,will try though.
Meanwhile the body temp issue - In general it's said approx 96.8 - 100.4 degrees F is normal fluctuation, 36 - 38 degrees Celsius. Depending on activity, early morning body temp may be a little lower. Everyone's metabolism varies so it's a guide.
Maybe a little hard to believe but due to what happened to me my body can't regulate blood pressure/temperature. Everyday my temp's will sit in the
93 - 95 (34-35) and have been checked as low as 91.4F (33.0C) even when trying to keep active. So my temp's can't rise unless there is artificial heat. I go passed the point of shivering without knowing it, the only indicator is lethargy and muscles start to seize up, slowing movement.

For you all though it could be normal or like me it's a blood/sodium issue and the way your body uses this. My bodies sodium level is low and not metabolizing properly.
Best wishes Nick