Hi ladies. Just really want to know.....

So my last period was 28th June ( think that makes me 12 weeks) went for a scan at 7+2 and the man came in and measured and said 6+2 then the lady (his second opinion said 7+2).... I have a scan coming on Thursday. And I'm trying to figure out if I will be 11+2 or 12+2 if that man was right? Just really confused as to what my actual due date is :( xxxx