It's quite common for someone who's blood sugar (glucose) levels that have been running high to experience hypoglycaemia [hypoglycemia, as I believe you're one of my American cousins] like symptoms when purposely attempting to lower one's blood sugar levels. This is because your body has become accustomed to these higher than 'normal' blood sugar levels.
Don't worry, these symptoms don't last for very long. Your body will soon adapt to having 'normal', or near 'normal' blood sugar levels again ... and it WILL be better for you in the long run. (It lowers the risk of you developing complications.)
Best of luck to you.