You may just be really early. Some people have bleeding in early pregnancy. I did from 6-15 weeks with my son and I went on to carry him to term. But I have also had 2 m/cs as well. Unfortunately, it can go either way and right now all you can do is wait it out. I would also see an OB and get an hcg and progesterone level test and follow up every two days to make sure your levels are rising like they should. I believe when your level reaches around 2000 is when they can see the baby on transvaginal ultrasound. Good luck to you.
I'm sorry for your situation. It's hard to say but to me it sounds like you could be miscarrying. Enough hormone could be in your body to be producing the positives on the test that you took after bleeding. It is very common in early pregnancy and happens more than people even think!
I very well could be wrong and I hope that I am. Many women do bleed in early pregnancy as well. It's good that you went to the emerg just to make sure though. Good luck and I hope you have better news on Monday. Take it easy for the rest of the weekend!