you should have taken Tab.Mifepristin before you used the cytotec
tbs. the cytotec tabs cause contraction of uterus
&expulsion of foetus. so, even if you change your mind, it may act late and cause bleeding/abortion/incompleate abortion.
So one has to decide firmly before taking such harmonal medicines whose action can not be reversible.
you should consult a gynac for further dosage (they will depend on action of previous dose/patient's physical condition.