No matter what has happened, and what your previous blood tests have been, it is not too late to make changes that will have a hugely beneficial effect on your health and your blood sugar levels.
The only thing you can change is now. So change. One thing at a time.
If you have a blood test in November, it will show you where you have been. Not where you will be next month, or next year.
Diabetes is something that we have to choose to control. And we have to choose daily. None of the decisions are particularly hard. How much potato? Sugar in coffee, or not? Do I take my tablets?
Each one is a tiny, easy decision.
We just have to make them consistently.
Regarding worrying whether it is too late. IT ISN'T.
Even if you have damage from high sugar levels, then taking control now (by making those first, small steps) can set you on a path where your body may be able to heal, or reverse the damage.
Don't believe me? Then read Dr Bernstein's Diabetes Solution book. He is a type 1 with quite severe diabetic complications in his 40s, who took control, and many (but not all) of his complications have healed over time.