elive that again 重复了,可以live that again 或 relive that;
but I could change anything I would be my lack of confidence 这句我认为应该改为:but if I could change anything that would be my my lack of confidence.
The reason why I failed was that I lacked confidence 这句应该保持现在时态吧
其他的我觉得没问题,写得其实还不错.