Am I or my doctor more accurate?

I've had irregular periods every since July when I had a D&C, from July to August they were 21 days, from August to September; 32 days. I figured my cycle was 32 days this month and figured it'd be here on October 29th. I took a test the same day and had an obvious positive, I thought I was 4 weeks at the time and today I thought I'd be 5 weeks, but my doctor based my pregnancy on a 28 day cycle and said I'm 5 weeks 4 days.

Question is, would I be 5 weeks exact or 5 weeks 4 days.

I've always had a 30 day until July 2015.