Yes, consciousness changes. I know a fellow (I worked with his wife in the past)..who would get up and take everything out the frig and couldn't open it and would eat anything he could get his hands on! Boxes of cereal...anything. Sometimes she would find him on the floor! His doctor never asked how his nights were...and I find that appalling.

Once the brain gets that low...and consciousness changes, you are way TOO low. There is evidence now, that lows this low,
damage the brain and lead to Alzheimer's.

So you really need to discuss your insulin with your doctor. Sometimes they reduce it at night if that is when you take your basal dose.

If your fasting sugar is high next morning after a nightmare...that is a sign of the somogyi effect and a signal to reduce bedtime insulin doses.

I think you should set your alarm for various times at night.
1am, 2am, 3am...etc. Some people depending on dinner and whether a snack at bedtime is taken, will show the fall at one of those times.
Set your alarm for each time until you find your dip and low it really is.

Some drugs cause vivid dreaming, and some B vitamins as well.