Empty geatation sack?

from my last period my fetus would be 5 weeks 5 days today so 7 weeks 5 days pregnant. yesterday morning i noticed brown blood mixed in with alot of clear cervical mucus, so went for a scan, when they did it they could see the gestation sack but no yolk sack or baby. i have another scan on 27th making me possibly 8 weeks 5 days fetus 6 weeks 5 days. im at a loss, im not having any cramps as yet but i did have a tiny amount of pink blood last night mixed with alot of clear cm. the dr said i had a flow in my tubes what ever that means,, any positive stories out there?