I saw ants on my underwears. not many but like 3-5 ants. i tested my fbs this month. the result is (103.37) the normal reference is 70-105 mg/dl. should i worry? is it pre diabetic?

Seeing ants on underwear is not a symptom of diabetes. Would suggest having a person you trust witness your symptoms, in your case what you see. Starting random testing will only complicate things instead of simplifying and clarifying them.

All laboratory results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Talk to the doctor who ordered the tests. Having said that, your blood sugar is consistent with a diagnosis of pre-diabetes. Try to lose 10% body weight and exercise 150 minutes/week. Wish you good health!