I am a 16 year old teenage girl and have had my period for about 5 years, very regularly. Recently since about July, my cycle has been very irregular, sometimes being 4 to 5 days late. I am sexually active and not on birth control, but my boyfriend and I do practice safe sex. I'm not exactly sure what to do or say, I'm just scared that I could end up pregnant or something that I do not have plan to happen for a while. I just don't know what to do, I just need advice please.