I am 18 and I am on birthcontrol. But I think its possible I'm pregnant. I've been on the bc for about 2 months. Me and my boyfriend started having sex about a month ago, never use a condom. I missed 3 days of my bc, and just realized it. The last time I had a period was the end of August into September. I was spotting (not really but there was little there) earlier this week but now its gone. (You've got to understand that my periods are normally a full blown ocean for 7 days) I have had the cramps and backache like I was going to start, including irritability. But nothing! I've heard that bc can cause false negatives on a pregnancy test so how do I know? Can't bc harm a baby? I guess my question is, what's the possibility of me being pregnant?