Thought 6 weeks told 4+6?

[Isit2021yetplease]

Thought I was around 6 weeks based on LMP and had scan booked as I wanted to check location and that there was just 1!
Sonography could only see a sac and said it measured 4+6. Could I really be a whole week different from my dates this early on? No fetal pole could be seen - which would probably be ok for 4+6 I think?
Has anyone else had similar? Knew I should’nt have had a scan so early but I am seeing an old friend this weekend who has struggled with infertility and miscarriage and so wanted to check all was going “ok” as will be obvious when I don’t drink, and I didn’t want to tell her if it was likely things weren’t going well, and then burden her with triggering emotions if I had to then tell her I’d miscarried soon after.
However now I’m more confused than ever.

It is common at the start to have estimated incorrectly. At my “12 week” scan I was only 11+2. Would recommend you avoid any more scans this early because it often just results in more anxiety.

This is common, try not to worry. I had an early scan at the EPU and according to my LMP I should have been 7+1 at the time, but fortunately I knew for a fact I hadn't ovulated as early as the LMP would calculate as. During that scan they measured me as 6+2 (even though I thought I was 6+4). I had a private scan around 8 weeks and expected to be told I was 8 exactly, but measured at 8+5. Try not to worry, from what I've been told by the midwife it's perfectly normal.

This happened to me!
We had a private scan at about 11 weeks where they put me back a week, then at the NHS 12 week one they put me back another day.
All's well now (as far as we know!) and I'm 24 weeks. Weeks 11-13 lasted ages though!