Infection does generally make blood sugars higher Ralph so it's highly likely that it had an impact. When you're body is stressed (including being ill) it shoves out more glucose into your blood because you need extra fuel to fix the problem. It expects your pancreas to up the anti too and shoot out more insulin to carry the glucose where it's needed. With diabetes though we've either got a pancreas that can't produce insulin (those of us who use insulin) or it can produce insulin but the body can't use what it's produced (most folk with type 2 fall into that category), so that bit of the process falls down and we end up with high blood sugar. That can also lead to longer infections because the body isn't as efficient at using energy anymore. The hba1c measures how much glucose is attached to red blood cells, it's a normal process in the body for some of the glucose to become stuck on the red blood cells, but if you've got lots of glucose in your blood more will stick to the cells. Red blood cells are constantly being made though, and they die off too, so the cycle is around 6-12 weeks depending on how efficient your body is. So the hba1c shows how much glucose you've had swimming around for the last 6-12 weeks, the higher the number the more glucose you've had in your blood.
Other things can impact on blood glucose levels too, more activity for example increases oxygen flow to the body and this makes the cells in the body more receptive to insulin (if you think of it as a door, the extra oxygen holds the door open which makes it easier for the insulin to get in), stress of any kind tends to play havoc with blood sugar, as does the amount of body fat you carry. Fat is a barrier to insulin, so using the door as an example again, body fat keeps the door shut and less insulin can get through, thats why they advise losing weight if you're carrying a bit extra, because the less body fat you have the easier it is for the insulin to get through the door. So if you've become more active or lost weight that could also help lower your hba1c.
incidentally generally the lower you can get that hba1c the better, because that means you're closer to "normal" blood sugar, and that helps to avoid complications. Good work getting it down since March, keep at it and keep asking questions 🙂. This post was longer than I expected, so sorry for rambling 🙄