I think you better go get a pregnancy test A.S.A.P, if you dont want to buy a home test go to a clinic and they do it for free. Bur even though you on the pill that don’t mean a thing really because I was on birth control and used condoms and I just found out im 2-3 weeks pregnant. Plus you mentioned that you was doing drugs!!! Thats not a good thing and maybe thats why your period is late also because you not suppose to be doing drugs while you on the pill either. But just to be on the safe side go get a pregnancy test done and stop doing drugs.