Considering your case history, I feel at the time of last reading you might have experienced more stress
. Stress also causes increased blood sugar levels.
Even more carbohydrate
diet intake can cause rise in sugar levels.
Have good breakfast, eat snacks between your lunch and dinner also.
Continue exercising, take 1 more reading after 1 month. If your readings still come high then you need to consult diabetologist
. Doctor will decide on adding other drug or changing drug.