Hi:

Yes this has happened to me....many times.  I have what my doctor called Unsymptomatic Hypoglycemia.  I ,like you, was at my doc's office. He was in the process of checking my blood sugar.  He asked me, how do you feel?  I said, I feel great why? Is my sugar high?  He asked me a few more questions and then said,  Your blood sugar is 24 !   Needless to say, he wouldnt let me leave without first drinking a glucose drink and then checking me again.

I was told that long term type 1's can develop a kind of neuropathy of the endocrine system.   

You are not alone in this, believe me.