When I was on the pill, I started it after my period began. Since you didn't, and you've only been on it two weeks-you should expect it during the white pill week.
Remember, while you are on the pill, it will stop ovulation- so the 'period' you get, the withdrawal bleed, happens when you are taking the sugar pills instead of the remaining 21 that have the hormones in them.
So right now, you're only on day 15. From now on, you should get it every cycle on day 28ish- with it starting consistently during that week of the white pills.