Blame it on Levi's

I got this pair of Levi's which is a combination of buttons (2) and then underneath it is a zipper. I only buttoned the buttons and assume that's all there is to it. Then I went on the MTR (TTC's subway) and STAND for the whole 40 minutes!!! Then at work I find out I forgot to zip up my zipper!!! >_< Ho Embrassing ah!!!!