At the past month I am having a daily dried mouth escorted by a slight headache and sickness, generally healthy. I drink water every day! ? Help!

Cannot diagnose. If you feel something abnormal is going on, visit your pcp and get examined.
Prediabetes ? It means that your blood sugar level is higher than normal, the symptoms are: increased thirst, hunger, weight loss, frequent urination. To rule out the condition see your doctor for the evaluation and blood glucose screening.