Recently I had my blood test which showed elevated FASTING plasma glucose 108 mg/dL. I never had sugar earlier nor it runs in my family. Past 1 year I had it checked 3 times and results were 85, 87, 87 mg/dL respectively. But now it's showing 108. Also my post prandial plasma glucose (2 hours) is 112 mg/dL. And result is negative. How come I have 108 fasting sugar with such low post prandial sugar? Is it a lab investigation error?