I am in fear of being pregnant. Me and the guy did use a condom but I still don't trust them. My period was suppose to be coming on the 17th of Sept. and now its the 26th. I had sex on the 18th. I did go to a doctor and they took a pregnancy test a week after I had sexual intercourse and it came out negative BUT I am still worried. Some symptoms I have are tender breasts. I do get cramps once in a while, and that's when I believe my period is on it's way, but it never seems to come. I am also constipated. I have also gotten headaches lately. What's wrong with me?! I'm extremely scared!