<s>[INST] Me and my boyfriend had sex last night. We were both under the influence of marijuana, and the condom broke and he ejaculated inside me. So we went around and got his dad to get me plan b one step, but I smoke cigarettes. So will smoking cigarettes effect the pill? And what will the marijuana do to me? [/INST] Hello, and I hope I can help you today. Neither smoking marijuana nor cigarette smoking will decrease the effectiveness of Plan B. If you took the plan B withing 72 hours of unprotected intercourse, there is only a 10 percent chance that you will conceive. It is not unusual to bleed slightly a few days after you take Plan B. This is a side effect of the medication and not your real period. If your real period is delayed, take a urine pregnancy test and if it is negative don't worry-Plan B can also delay your period for a week or so as a side effect. I hope I was able to adequately answer your question today and that this information was helpful to you. Best wishes, </s>