Have you had an ultrasound with a low fetal heart rate and gone on to have a successful pregnancy?

I have been having some bad cramping with no bleeding so I went in to see my doctor yesterday. They did an ultrasound in the office and the baby had a heart rate of 104. We are still really early (estimating 7 weeks) but the baby was too small to get accurate measurements to date how far along I am. They didn’t seem very hopeful with the cramping and that low of a heart rate despite the fact that I’m not having any bleeding and my cervix is closed. Has anyone had a lower heart rate at an early ultrasound and gone on to have a normal pregnancy?