Blighted Ovum / ectopic pregnancy / miscarriage

Hi everyone, I’m looking for stories on the above topics if possible I had an early sven yesterday, privately, where they saw a sac but no fetus. They immediately referred me to an early pregnancy unit, as it could be ectopic, blighted ovum or most likely I was just too early for them to see anything. I should have been measuring 7 weeks, and this was a place specialised in measuring early pregnancies so surely they’d have seen something, right? I’m under the impression I’m having either of these conditions from what they said, but today I’ve started with cramps and going to the toilet a lot (TMI sorry) and I’m unsure if this is the start of a misscariage I have had a miscarriage before my daughter was born, and it started while I was asleep and I have no idea if what I’m feeling is the start of a loss or something else… Any advice appreciated