Okay, so I'm pg but I'm not sure of my dates. (And GP didn't do bloods when I got a referral)

I wasn't charting properly so I'm not 100% sure of when ovulation was. I suspect it was the last few days of July though, going on CM. If I go by my LMP I'm about 6wks+3days, if I go by my "averaged" cycle length of 37 days (cycle before this one was 71 days) I'm about 5wks+1. That's just using the standard 14 day LP. Before DS was born I had a 12 day LP. This time I'm not sure as I've still been BFing DS and I wasn't charting due to his random morning wake-ups.

I've got a referral for a dating scan for my Obs but was wondering when I would be best attempting to book to have it. I need to have the scan before 15 Sept as that's when my first appt is booked but depending on my dating scan that appt might change.

Should I be waiting another week so I'd definitely be in a 6wk+ timeframe (so not this week 22/8-26/8 but next week 29/8-2/9)? When is it best to go for a dating scan 6 / 7 weeks etc? I know I only had one at my first appt for DS but I was clear about my EDD for him.