... GP thinks my dates may be 2 weeks out. Is this even possible? Both my scans have dated me to be as pregnant as I thought I was and surely if I was 2 weeks out it would mean I conceived whilst on my period?!?
Even if you're measuring big, it's unlikely your date would be changed. The latest they change EDD is around the 12w scan. After that, your EDD is pretty much 'set' so I don't know why your GP is suggesting your dates are wrong, he/she should be thinking about other reasons for you to be measuring slightly over what is expected.
Ideally you should be measured by the same person at every appointment, as different people can bring up different measurements.
+/-2cm is considered normal anyway. Any more than that and usually they'd offer you a growth scan (followed by another a few weeks later) to check size and if baby was showing to be big, then they might offer a Glucose Tolerance Test (GTT) to rule out Gestational Diabetes. However, even then, the scan can give estimated weights that are out by a lb or 2. DS was estimated to be 9lb 7 - 10lb 7.
He was 11lb 7oz.
Others on here have been predicted a big baby, and have come out with a tiddler!
I wouldn't worry too much about fundal height measurement- unless there was a big difference between the number of weeks pregnant you are and the centimetres you're measuring. At 39 and 40 weeks I was only measuring 37 (and baby hadn't engaged), and DD was 8lb 1.5oz. A friend of mine was measuring 42 at 37 weeks, she then went into labour a couple of days later, and her baby was 7lb 5oz.
I measured big on my first pregnancy so had a private scan which showed I had excess amniotic fluid and that DS was a big baby. Turned out I was borderline for GD and DS was born a bit jittery with low blood sugar which meant the hospital insisted on giving him formula and if took me longer to establish breast feeding. Always worth getting checked, if your GP is dismissive ring your midwife directly or call the antenatal unit.