Key Key Key

I do not know why today is so bad luck for me. Maybe i done something wrong by last few days. Haiz haiz haiz, i regret that i changed my keys with my mother and did not look properly when my mother was changing the keys. The key is my locker's key, i have to open it to get my shoe, name tag and belt. Yesterday(6/6/2009), i already asked the security department to open the locker for me and get scolded by them. If today, the same thing happened and i will get warning letter for sure. If my mother come back yesterday, all this would not be happen again! I just work for few weeks only and got so many problems already! how can it happened to me? What i had done? Hope this problem will not occur again!