My LMP Was 2 Sep. , Im Pcos Patient, Preg

My LMP was 2 sep. , im pcos patient, preg test was neg., my gyne. Suggested me meprate , I was take it in 25 oct. To 30 oct., after this we hv unsafe intercourse, still my periods nt cm, there is chance of pregnancy?
Nd my periods alws delay abt 40 to 60 days...