Welcome to the Forum, emuhhlee. I'm really glad you found us and even happier that you have decided to get your diabetes under better control.
Yes, someone who's lived with very high blood sugar will probably experience strange symptoms when their blood sugar comes down to normal levels or even just lower but still elevated levels. I'm not a doctor, but I would suggest to do this gradually over a period of days to allow your body to adjust to the better levels. You might feel shaky, have headaches, dizzy along with other symptoms. What does your doctor suggest?
Since you're on insulin, you know you need to test quite often. As far as food, eating a lower carb diet would allow you to use less insulin in order to maintain normal (or near normal) blood sugar levels.
You must know that very high blood sugar over a period of time can cause kidney failure, heart problems, blindness, neuropathy. You can save yourself from these health complications and have a longer life by making sure your blood sugar is well controlled.
I recommend Diabetes Solutions by Dr. Richard Bernstein. He is a type 1 diabetic and his book covers everything you need to know.
Also, here is a website with lots of information: http://www.bloodsugar101.com/
Please continue posting. We have other type 1's here, too, and I hope they respond.