My Periods Were Due On 20th Dec & Its 12th

My periods were due on 20th dec & its 12th Jan now i didn't got periods...i thought may be i hv conceived so I took cytotac 2 tablets also took boil egg with strong coffee after tht but bleeding did not started....the next night I took another 2 tablets not cytotac (i don't know the name of tht tab) which I inserted inside vagina with the help of tube but then also no bleeding started....i am still wondering what could be the cause of no bleeding?