Brown speckled discharge?

I started bleeding heavily with a lot of pain coming and going at 10 weeks and 3 days. The bleeding lasted for about 3 hours and stopped. I went to the hospital they said its a threatened miscarriage but the baby looks healthy. They had no answers for me. I cant see my OB until Monday. Since then ive been having off and on brown discharge.

I noticed the discharge has tiny brown specs in it every time. I'm 10 weeks and 6 days today. No pain since the bleeding stopped. I keep checking the babys heartbeat and its still strong. But I cant figure out what couldve caused the random bleeding. Or what this brown speckled discharge could be.