Hi Sascha, welcome to the Forum. Well done for giving up smoking. Have you been eating more since giving up smoking? If so, this could be the reason for the increase in your bg. Also, giving up smoking can slow your metabolism down initially.
I find that doing some exercise, like going for a walk lowers bg. Do you have a meter and strips?
Complications occur usually after many years of uncontrolled high blood glucose levels, which is why it is important to test your bg regularly.
Sorry for all the questions, but it helps to have a bit of background information.
Marilyn