Gestational diabetes

I was diagnosed late with gestational diabetes at 30 weeks. OB told me to go straight away to the endocrinologist to discuss if I will be taking insulin or not. When I went to the endocrinologist, she told me to go on a certain diet low in carbs and to monitor my blood sugar level once when I wake up, before eating anything and once 1 hour every after meal. She told me I can't go above 140. She also adviced me to go to a dietitian to talk about food I can eat and how much. When I went to the dietitian, I was met by a nurse who gave me a list of food I can eat, how much and carb intake every meal. But at the dietitian's office, I was told I should not go above 130 after each meal.

My question is, I have been doing this for 2 weeks and so far, my blood sugar level after meals have been good, ranging fro. 83-115 (my fasting sugar level ranges from 70-85 which is always below). But, last week, one of my result went up to 133 (above the dietitian's range but still below the endocrinologist's) and now my blood glucose level is 140.

Would it be a cause for concern even if it was just after 2 meals within a week even if most of my results were good?