What Causes Sore Breasts And Irregularities In Menstruation?

My breasts are very sore and have been for a while and they have been growing, I am already a D cup... I have had to go to the bathroom about every hour. and this last time I went to the restroom I was bleeding a little bit. I am very irregular and my last period was Jan. 27 - 31. And it took 7 weeks to get that one. I took a pregnancy test and it said negative but the line was extremely faint.... Could it be a false negative?