What is YOUR "diet controlling"
my diet is under 50 gr of carbs a day with 55 Iu of insulin.
What is your "medication" and how much are you taking? What are your preprandial levels? If preprandial is close to normal, then your diet is not controlled as indicated by your postprandial level. If your "diet controlling" includes no sugary foods or liquids, no white rice, no potatoes, no foods made with white flour, minimum carbohydrate intake, and you are at normal body weight have your doctor check your pancreas insulin production. This includes an islet cell C-Peptide test. Good luck -
This level of FBS and Post prandial blood sugar will cause severe complications if it continues.
If you can't control with diet (low carb works best) and oral medication, and exercise, it will be recommended to use insulin. Insulin is a powerful and very useful medication for diabetics. It is not to be feared, but you will need to learn to use it safely.
Normal HBA1C is in the 4s or low 5s. 7.5 is well above normal.
Truely normal fasting (is in the 80s) and 2 hours after eating should have returned close to fasting level. Your numbers are very much above this.
Even if someone is diabetic the objective is to ideally keep blood sugar below 140 at all times to prevent complications. I am telling you this so you can see what your targets are.