B.C.
It could be. Everyone's different and although many start in their mid 40's, some do start a bit earlier and a few a bit later. On the other hand, some people have irregular periods all their life, so a few months off the usual schedule might not mean too much. The event that convinced me I was starting was when I had my first hot flash. You're completely menopausal when you've gone a full year without a period, but it can take some women 10 years to get there with all kinds of irregular periods in the mean time.