Threaten miscarriage

Has anyone had one? Sunday and Tuesday I was spotting for a hour very light and not constantly during the hour then it stopped no cramping no clots so I figured it was implantation bleeding. Wednesday full on bleeding from 4-9ish filled a pad and a half with red blood no clots nor cramps so I went to urgent care they did various ultra sounds and saw a yolk sac but no heartbeat they think it could be because I’m so early, so I go back in a week in hopes to see a healthy beating heart and some development. Has anyone experienced something similar? I’m trying to not lose hope but anytime I think about it I cry, if you pray please pray for me and my baby! Only spotting off and on since Wednesday. 😩💛🙏🏼