Periods gone a bit haywire lately? Not sleeping the way you used to? Some days your mood just tips over for no reason you can name? Chances are perimenopause has already started, even if nobody's actually said the word to you. It can begin years before your last period, and at first it barely looks like anything at all. Just a rough patch, a stressful month, a bit of bad luck with sleep. Most women don't clock what's going on until it's been happening a while. Here's what ten