Yes, a complete random blood test would surely have shown high glucose levels, for glucose counts are one of the most common things tested in random non-specific bloodwork. Do continue to talk to your doctor, though, about symptoms that aren't normal, and be specific about what they are.
NotReallySure,
We're volunteers here and not medical professionals, so do stay in touch with your doctor.
If your doctor did a random blood test & the results came back normal, that's good information adn should be reassuring to you. If you have a set of symptoms that you can't explain, I urge you to talk with your doc about those symptoms specifically. It can often help to keep notes for a while on how you're feeling at different times of day, your activity levels, foods, stresses, emotions, etc. We can use that info with our docs to help identify patterns that they can help us interpret and/or treat.
Good luck.