Missed period for 2 cycles - not pregnant. What could it be?!

Missed period for 2 cycles - not pregnant. What could it be?

I had a baby in 2006. After 6 months my period returned and I went back on the pill. Two weeks after starting the pill, I had a 7 day period (in the middle of the packet of pills). Two weeks later when I was supposed to have a period, I had another 7 day period. This repeated the following month. Then I went through TWO packets without a period. I've taken multiple pregnancy tess - all negative. I have an appointmet with my dr next week. But in the meantime - any ideas???

Polycystic ovaries? You'll usually show other signs though, like excessive hair, weight gain, greasy skin.
I think your hormones do mess up for a while after having a baby, but it sounds like this is something your doctor should test for as it could be something else, or nothing at all.