I had a early scan to see the HB at 8 plus 6 and then again at 10 weeks, as I had a missed Mc in march at 11 plus 5, because of the dates I lost that one, I still carried on worring, so may be worth waiting till later on when your really desperate if you have to pay.
Try to spread things out in tri 1 tok use as little milestones to get your to 12 weeks quickly
Eg wait and see docs at 7/8 weeks, midwife for booking in at 10 weeks, then scan won't be long then