There are lots of things that can cause low body temperature. Yes, low blood sugar is one of them, kidney failure is another, low blood pressure is another, dehydration is another and the list goes on. As far as the whining goes, pain, discomfort, confusion, anxiety, hunger, thirst, etc all come to mind and makes me think that there is a basic need that is unmet. Yes, it could be confusion or fatigue from low blood sugar but that is not the only cause.
As you know the best way to know what is going on with her is to have her examined by a veterinarian as I am very limited without a physical exam and there are only so many things that we can do at home without hospital equipment. Addressing a possibly low blood sugar, warming her and making sure that she is drinking (and ideally eating) are the best ways of helping her until you can get to a veterinarian and pay for treatment.
The best thing to do is to provide an external source of heat until her temperature is normal. The normal temp of a dog is 100.5-102.5. You can take it with a rectal thermometer and stop heat support when her temperature reaches 100 as we do not want her to overheat. If it drops back down, then you can re-institute heat support.