Has anyone ever been misdiagnosed with a miscarriage?

I know that this may be an accurate diagnosis, however I just wanted to ask the community to see if anyone has ever had a similar experience to this and was misdiagnosed as a miscarriage.

Two weeks ago I had my first ultrasound at six weeks and there was a visible heartbeat on the monitor however it was difficult to pick up audibly and when it was picked up the heart rate was only 62. In fact when I went in to this facility for a second opinion the day after I went to the ER I was told that the overseeing OBGYN of the clinic wanted to rescan me because when reviewing my ultrasound he believed the heart rate was low for my gestational age.

Two days ago I went to the ER for a severe anxiety attack, I was given an ultrasound and was told they couldn’t find a detectable heartbeat and since I am about 8 weeks they diagnosed me as a missed abortion. (keep in mind the visible heartbeat at six weeks) I was diagnosed by a PA, radiologist, and ultrasound tech collectively, no OB review

I went to the clinic where I first had my ultrasound at six weeks so I could get a second opinion and actually SEE the ultrasound screen. Did not see exactly what I saw last time, but the ultrasound also seemed less defined and I couldn’t really see anything. The ultrasound tech said although everything is in my uterus, they weren’t picking up cardiac activity. Again no OB diagnosis here either.

My OB wants me to get a blood draw tomorrow to compare it to the blood draw from the hospital and see if my levels of hormone are dropping and also do another ultrasound in a week.

I’ve had no bleeding nor spotting, no cramping, no abnormal symptoms, still very on and off emotional mood swingy. I feel my nausea has depleted since the diagnosis but this happened immediately after my hospital visit so it could be purely in my head, and I was very nauseous again this morning and on and off through the day.

When I talked to my OB’s nurse she said a lot of the time they don’t do ultrasounds til 8 weeks anyway because the machine isn’t powerful enough and it can be inaccurate and she also said it could be that my timeline is just off and I’m less pregnant than we thought. Although I’m a little concerned with this theory because of the visible on screen heartbeat at my 6 week ultrasound.

What do you guys think? Have any of you had a similar experience?

Please be honest and don’t sugarcoat anything, I really do want to be prepared if this may end in bad news but I also really hope everything is okay.