How Long Does Cytotec Take To Terminate Pregnancy?

I suppose to have my period is the 18th of January so I went to a dr and did the ultrasound and find out I am pregnant. I don t want this pregnancy so he graves me cytotec. This is my 3rd day and there is no blood is that normal?and how many days does cytotec need to abort the pregnancy and for how many other days should I stay on pills.?