You won't know till your 12 week scan hun as babies grow at different rates till 12 weeks so could appear weeks behind then at 12 week scan he/she would be the correct size and the right weekage you are x I had early scan at 8 weeks and 2 days. They estimated me at 7 weeks and 6 days. So that was three days behind my ticker then at my 12 week scan baby was bang on so it was a waste they did say they don't date before as baby grows randomly also the image was terrible. I was just glad there was a baby in there.
Have you thought about getting a private scan? x