What Causes Delay In Bleeding After Taking MTP Kit?

Hi doc I am 6weeks if pregnant n it was early pregnancy after my first baby so we plan to abort it before situation gets worst n on gyneac advice I started MTP kit yesterday 11:30am I had first dose if it mife 200mg I have in take orally but still I did not start bleeding m worried please advice let me know when usually bleeding starts after using MTP kit