"I am stupid..."
no no no. dun ever say that you are stupid.
you are smart, but just that you are not as smart as other ppl. believe in yourself. if you think you can, you can.
"i thought u are the one last time who said you can cannot do this and that?"
"that was last time. it has passed."
i agree that the person has grown up and become more mature in thinking. congratz. you have learned frm mistakes. you have tried to improve yourself. and now u have the confidence in doing what you are doing. trust yourself. everything will be fine.