Another Disappointment

Today I got back my mathematics results and my economy objective marks. It is really very very disappointed and meaningless. What happen to my mathematics? I'm chinese. I must get A for mathematics. Chinese should good in calculation. But I get 60++ for my maths. It is so shame. I want A for my Maths please. I done a lot of practice for my maths. Why can't I get a better results? Everyone said practice makes perfect. Is totally bullshits. I don't believe anything now. I believe to myself only. I done so many practice the results is still the same. I rather give up. I don't want to forced myself. Sometimes I really don't know what happens to me. Sometimes feels very confident sometimes feels very nervous and scared. I really felt like somethings goes wrong with me.