I am sure bub is fine hun. A few days either side of the date is normal - remember that due dates are always only approximate, so bub measuring behind this date is not necessarily anything to worry about. With my first two babies they actually changed my due date, adding 7 days, because bubs didn't measure with the due date based on LMP. So they were measuring 7 ish days behind dates. When they were born (one at 38 weeks due to pre eclampsia and the other right on her due date) they weighed 7lb 10oz and 7lb 9oz respectively. So basically an average weight, not small and not big. The only one of my babies to actually match with her due date at the ultrasound ended up being born at 41 weeks and weighed 9lb 9oz.