Hi, I ve been on depo for awhile now, August will make a year, and when I first got on it I bled off and on until November then I stopped and haven t really bled since, well my best friend is pregnant and she always has Tylenol on her and so one day my back was really sore from work so I took one and then and hour after I took it I bled, and I ve bled off and on since but it was the day after I had my doseage of depo, so I was thinking it was just because I got my depo, and it goes away but then today I noticed it s gotten heavier and darker... What does this mean?