Need help

Im 24F. I don’t know if i did it right. Hindi ako nagppills before but I had unprotected sex last january 30. My bf cum inside me. (Yes its stupid) It was 2days after my menstrual period. Regarding to flo my ovulation starts at Jan31. Before 72hrs i took Diane pills 3pcs sabi ng friend ko. Hindi ko agad natake kasi wala akong mapagbilhan agad. Then took it everyday. Now ubos na yung pills ko at di na uminom. Supposedly my menstruation should be feb 18 or 20. Its already 23 and wala parin akong mens. Ubos narin pills ko and not taking na. I took PT last thursday its negative. Then i took it again today its still negative. I wonder if hindi lang ba accurate yung PT or is it bcs of Diane pills? I know its so irresponsible but please someone help me.