I just got off of the pill and went on the shot, but when I was on the pill I would normally get it at the end of the 4th day on the sugar pill. Sometimes a day earlier or a day later. Your body may still be adjusting to the change. I wouldn't worry unless you don't get it by the time you start the next round of pills.

Some pills have hormonal levels that cause you to skip your period altogether. Or just every couple of months. But, since you just switched, and if you are sexually active, you may want to take a test just to make sure. But, if you are not then give it a month and then just ask your doctor to make sure it is normal with the pill you are on. Hope this helped.