I don't know what happened to me?

I think the problem is, you have lost confidence in yourself and have become a mere shadow of your former self. It's all downhill from here.

If you were a college student they would be calling that burn out. But I take it you're not but I think the basis is the same. You are having a lack of exercise. When that happens waste products aren't moved off the body and back up. When they back up they hamper body functions because there is no place to dump the waste products. Then those body parts become filled with waste product because it can't get rid of it and the required nutrients can't reach it or go in because of that and now it is going to hurt more because it can't function any better than it did before. And this can go right up to the brain and create learning or recall problems there.

It happens sometimes. Just slow down a tad bit. It takes a little more sometimes to ace tests.

Take a look at the math paper again and see the mistakes you made. Analyze them and ask yourself why you did not get it right. Learn to ace the test slowly but steadily. Practice and answer mock tests. Do not worry about your confidence. It will come back as soon as you start figuring out to do well in such mock tests.

Repeat these in other areas as well. Watch the magic come back.

You asked the question yourself - what happened? Was there an incident? Perhaps how your parents or friends reacted to you winning? When you uncover the reason, you'll be able to rebuild your confidence.

u just think that there is no problem with u and study well. bring back the confidence on yourself.

well, when u get older u go through puberty. the chemicals ur brain produces slightly changes too. it's kinda hard to explain. i read it somewhere and i can't remember much but don't worry though. hopefully, you'll get back in track.

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