Dark Brown Blood

So from I was 10 weeks and 2 days, I got a big scared when I went to pee and saw blood on my liner and in the toilet. Went to the er immediately and was examined the baby was ok nothing was coming from the sac he/she is in (Thank God!) But unfortunately the gynecologist can't say what causes the bleeding. The bleeding subsidies and I only start spotting. My point is it's been like that until now am 13 weeks and 2 days today (the blood is now dark brown) going to see my gynecologist later in the day. Am not so scared because she told me maybe is old blood and my 12 weeks and 2 days scan showed that I have fluid of 3.5mls. And a small subchorionic haematoma. Keep me in you all prayers. (FTM)