Am i? Should I be worried?

All forms of hormonal birth control can cause unpredictable spotting, especially when you first start and your body is getting used to the hormones. As long as you are taking it correctly (taking it every single day without skipping any pills, taking it at the same time every day) then you should be just fine. Yasmin is very effective birth control. If you have a real fear or concern that you are pregnant, talk to your doctor that prescribed it. But really, three days after is too early to have any pregnancy symptoms anyway. Good luck!