I test my blood sugar once a month, my father is diabetic and i am obese. always come back normal but this month it's been 2 days that i'm getting 114, 121 and those are not the usual results i'm not diabetic yet, should i diet? see a doctor? meds?

Do Both. The data you provided, if it fasting plasma glucose, is consistent with Pre-diabetes. Losing at least 10% weight and exercising at least 150 minutes/week has better than even chance of preventing diabetes. It would be useful to consult a nutritionist for diet advice. Wish you good health!

The best think to check is the HbA1c. This is considered to average the blood glucose over 3 months. The best way to prevent diabetes is to get your BMI to 25. You need to decide if it is worth doing what it takes to do this. I recommend the DASH eating plan. Best of all eating plans.