Bloodsugar is 170, is that bad?

I take metaprolol for low blood sugars. I never have high blood sugars. Lately I have been getting really tired and feel thirsty all the time. Today I ate subway at lunchtime at around 6 I was coming home from the store and got so sleepy driving. I decided to check by bloodsugar and it was 170. I hadn't had anything to eat in over 5 hours. Is this bad?