Let me start off by saying that there ARE women who bleed throughout their pregnancies and they carry full term healthy babies. The reason why I know this personally is because I miscarried around this time and I remember asking my aunt who has 10 healthy adult children if it ever happened to her and she said yes. They did not (mostly) result in miscarriage and there never was a known reason why the bleeding was caused.
I know it can be very nerve wrecking and either way no matter what, I just want to share a thought for whatever its worth. When a pregnancy is terminated for whatever reason, there was something wrong with the fetus. If there is just bleeding and you carry on normally then hopefully everything is fine with the baby and its development. But if things don't work out and the pregnancy does not succeed just know in your heart of hearts that it was not meant to be and that it was better for everyone. It is hard raising children who are healthy let alone children with more than the "norm" needs. So, that being said, hang in there, trust in nature (and G-d if you are religious) and know that it all is for the best. Good luck and keep that chin up! It'll be okay.