It does sound like low blood sugar, ruling out the dehydration. I'm still working on the blood sugar numbers, as they went the higher way. Good you're doing this program now so you won't get the diabetes. I'd say keep some fuit juice handy for times when you feel light-headed, sweaty or weak. Fruit sugar is good or some form of glucose.
I've been looking at how I am suppose to keep my body aligned when I sleep. From what I hear, sleeping on the stomach isn't good for the neck. You're supposed to lie on your side with your nose lined up with your belly button and knees bent up a little? Try to keep that one in place!! I had to lie that way for a long time with a slipped disc in my neck. You can put a pillow between your legs and it's more comfortable or sleep on your back. That's a hard one to change since we find our own way of getting comfortable when we go to sleep.