Think my due date is wrong by 6 days

My due date was yesterday which was based on last period (5th March) assuming that it’s 28 days. However my cycle is 34 days and I was doing ovulation tests so I know I ovulated on day 20 not 14.

I did mention this to the sonographer at my 12 wks but they said baby was measuring to the current due date (based on 28 day cycle). Not sure if I should in my head be expecting it to be this weekend rather than yesterday.

I did however get a positive pregnancy test 10 days past ovulation (first one i took) so I don’t know if i implanted early and that is why the baby was measuring ahead?

Basically I just want reassurance 😂