I have been on yaz (drospirenone and ethinyl estradiol) for two years and selected when to take sugar pills (not often) im on them now (on 3rd day) and sill no period. what does this mean?

Not a problem: Long-term use of a low-dose birth control pill (like Yaz (drospirenone and ethinyl estradiol) and others) has a temporary effect of making the uterine lining very thin. Therefore when the "break" is taken for the placebo pills there may not be much if any uterine lining to shed. This side effect is harmless and should be enjoyed while you can! once you stop the pills and normal ovulation resumes, the bleeding will return.