implantation bleeding or aunt flo

according to my apps (Yes I have 3 ) I was 2-4 days late. took 2 test and both said negative. not 100% sure when I ovulated.....expericing light cramps, sore breast, a little ache, let cramps, bloating and slight headaches with a stuff nose. I got what I thought was aunt flo but it is a brown discharge like that is light. I mean I could wear a tampon all day and it not be soamed. this is day 2 of this and aa frie d said it might be implantation bleeding but I am not sure. What do you think