I got measured to be 10 weeks 6 days instead of 10 weeks 3 days and baby was 4.03cm... The tech said baby is measuring…

I got measured to be 10 weeks 6 days instead of 10 weeks 3 days and baby was 4.03cm... The tech said baby is measuring big and that their still gonna stick with my due date Jan 16 til i see my doctor July 25. And and she said she was gonna also still stick with me being 10 week 3 days. This all happened thursday.. I'm still confused.. I ovulated between april 24-28th. I had pains april 25&26; on my right side and clear stretchy stuff April 28th. Last PERIOD WAS APRIL 11 but a weird period. I spotted after me and my bf had sex . Then April 12 it was more blood then slowed down with a little brown April 13 and i woke up April 14 there was nothing anymore. My period usually be heavy and last 7 days.Someone help me here.TODAY IM EITHER 10weeks&5days; or 11weeks&1day;