I think you care too much about math to let go psychologically. You have heard of the "acupuncture effect". In other words, psychologists have done an experiment. When wearing a dressing needle, the more attention you pay, the more difficult it is to get in. This "needle-piercing psychology" is called "eye trembling" and "needle-piercing effect" by the scientific community. Life is the same as study. The more serious you are, the more successful it will be. Mathematics, know theorems, understand examples, and draw inferences to do the right questions. It's not that I can't do the problem, nor that I don't know math, but that I'm too different from math psychologically. Of course, proper care is beneficial, but too much care is not conducive to your study.

When you review the theorem, try to give yourself some psychological hints: well, you have mastered it. Try to do some exercises. Look at the review results. I believe you can, because from your questions, I feel that you study hard. I hope you can learn to live a little, so that you won't be too tired and you can grasp your grades well. Come on! !