I haven't washed my face with a cleanser in almost 2 weeks and my acne has improved... how?

So about 2 weeks ago was when I got back from my grandparents house, and now that I'm sitting at home doing nothing I've gotten really lazy and haven't washed my face at ALL. And so a few days ago, I look in the mirror and say to my mom, "Hey, does my complexion look better to you?" She says, "Yeah, what have you been doing to it?" And I look at her- and I say absolutely nothing. And of course she said that not washing my face would normally cause acne to get worse, since, you know- the dirt and oil build up on it and cause the pores to become blocked. The cleansers that I was using on my face before did not cause my acne to get WORSE, but really my acne just stayed the same. Anyone have any ideas on why is this?