Threaten miscarriage

Has anyone had one? Spotted both Sunday and Tuesday very little light pink no cramps and no clots Wednesday red bleeding went through a pad a half and spotting here and there since. Had a ultra sound but all they saw was the yolk sac they aren’t sure if theres no heartbeat seen yet because I’m still so early so I have to go back in a week in hopes there’s a healthy heartbeat. Trying to stay positive but it’s so hard to anytime I think about it I just want to cry, please pray for my baby and I.