confusing ultrasounds???

so i had my first ultrasound at 7 weeks transvaginally and measured exactly that making my due date 6/12/19 well then i got this ultra sound abdominally last wednesday expecting to be exactly 9 weeks and apparently i measured at 10. but from what i’ve seen of 9 and 10 weeks my baby looked like the 9 week ultrasounds. what do you guys think? which ultrasound would be more accurate?