@bluebell94 - I had an early scan with my first baby (Around 5.5 weeks) which we lost. Wish I hadn’t as it was way behind on dates and I KNEW not all was well even though we saw a heartbeat. Turned out was right and had a MMC at 9.5 weeks.
With second baby (he’s now 18 months) we ended up having a scan at 8 weeks because had awful sharp pains (which turned out to be wind!)
Now 6 weeks with number 2 and am going to go for one at 8 weeks because we are getting Iona test at 10 weeks and I don’t want to waste the cash if it’s not viable. Also, at 8 weeks you can see a lot more. At 5-6 weeks it’s really just a sac with a heartbeat.
So my advice would be 8 weeks is a good time for an early scan x