I had breakthrough bleeding too mid cycle - around day 11 or 12 of my cycle, which is weird. I had been on the pill (this time) for about 3 and a half years, before just coming off on the 15th of this month to start AF on the 18th so I'm just going to assume it was "adjustment" bleeding, as it is way to early for it to be the big O bleeding - normally when I'm off the pill, my cycle is around 29-30 days. Though, when off the pill, I've never noticed break through bleeding ever before, so goodness knows what it was =) Body does wacky things when you first come off the pill!