I'm not sure what Type of diabetic you are Kendal but I'm assuming that you are Type 2 and possibly on tablets

Your drop in blood sugar during the day is purely based on exercise. Your body is using more glucose (as energy) than you are taking in as food. Your overnight readings could be normal FOR YOU,

OR

If you are taking tablets - and take them first thing in the morning - their effect could be wearing off overnight. Try taking them at midday and see what happens,

If you are taking tablets there are two kinds ,,,,,,,,

One encourages the pancreas to produce more insulin
The other encourages the body to use the insulin produced more effectively. If not already on both - you may need to change.

I apologise if I am totally off beam with my assumptions but it's taken me 13 years to sort out my own needs as a diabetic so I know it's not easy.