I can especially understand your feelings, just like I did at the beginning. In fact, there is still a long time before the exam, and the later the more important it is. From now on, you should start answering questions at 8: 30 every morning according to the time of the math postgraduate entrance examination, and strictly follow the time. Just like an exam, if you don't have enough time, you will have a choice, which to do first and then which to do, and then you will find that after a week or two, the speed will start to accelerate, which will train your exam ability.
Time is up, get the answer, and analyze what kind of questions you have done, which delays the time, indicating that the knowledge in that area is not solid enough. One day, I will concentrate on doing that problem.