What Causes Delay In Periods?

hello doc,im samantha,24 yrs young. im taking daphne pills for the month of september and supposed to be my menstruation will start at october 27,but no mens occured,so i just stop taking the pill coz i have read many comments here in net that they also feel the same way.im worried about this,but is it ok if i switch to other contraseptive pill even if menstruation does not occur yet?