Indeed, phone your surgical team to get their advice.
Because even though your hba1c levels, it is possible that you have now started to eat more unhealthy for you as you should.
It could be indicative that you need to use the drug to get it back down.
Has your doctor advised you about dietary restrictions regarding carbs, sugars, fats and proteins? That is why, I have advised to get in touch with your surgical team rather than your GP.
Of course, I cannot diagnose, but I would not rule out reactive hypoglycaemia, as it can occur after surgery.