I've been on ortho tricyclen lo for over a year now and i've had no problems, or worries. Sometimes (not all the time) the reason birth control fails is because it isn't taken properly.
If you're late taking it all the time, or miss pills constantly, then you may get pregnant. But if you're taking them on time every day, your body won't build the lining it needs to get pregnant... Or something to that effect.
I personally like ortho tricyclen lo. Lower hormones and lower risks of blood clots, stroke, etc. And, my cycles are anywhere from 2 to 4 days and super light!! :wink:
but everyone is different and it's important to find what works best for you. If you're uncomfortable with your current pill, i'd definately talk with a doctor!