my bf and I had sex on Jan. 15th 2011.. Although we used the pull out method, he is known to produce a lot of precum. On Jan. 18th when i went to the bathroom I saw that there was a little blood then it stopped. On Jan 26th, I was bleeding for half a day. I took a prego test on the 24th and it came back negative but because i only came on for half a day on the 26th, im thinking i may be prego, but im not sure. any help?