Today I took a home pregnancy test (e.p.t) because I am four days late. The result was negative. But I do not remember my period being this late before,although my periods are never regular. I use to start around the 5th of each month and now for about a year I have been starting on the 28th of each month. I am not having any symptoms, my last period was the 28th of September. Then I had sexual intercorse around October 12 or 15th, we did use a condom but before he put the condom on we messed around for a couple of minutes but he did not come before we messed around or inside of me at all. After maybe about three to five minutes we put a condom on and continued. So I was wondering if the pregnancy test should be pretty acurate or would it be to soon? And also I have been taking b12 vitamins,now would be the third month taking them,could they make me late on my period? I was slightly anemic that is why I had to start taking the shots. Thank you so much for your help.