Glucose rising day 12.

My husband and I got a glucose meter before beginning our fast. We tested at the beginning of day 1 and were in the normal range, 93 for him and 92 for me. I expected our glucose level to drop substantially while fasting, and it did for a while... day 5 we tested again and he was 76 I was 89. Now, at day twelve we are both over 100 (102,103). Is this normal? Is it something to be concerned about? We are doing a true water only fast, ingesting nothing else.