Well, of course it could be possible that the midwife is mistaken. It could also be possible that the embryo isn't growing as it should, but I wouldn't leap to that conclusion without two beta hCG tests 48 hours apart. Another point is that although you had sex on March 19, that does not guarantee conception on March 19; it could be as late as the 25th from that event, since sperm can live a while in your system. Were you using ovulation test kits? Another possibility, if you kept having sex after March 19, is that a first pregnancy began and faded (chemical pregnancy), and you ovulated again and a second one began. Don't know what to tell you except to have two hCG counts done 48 hours apart, and see if the count is still rising at the appropriate rate. If so, subsequent ultrasounds should clear things up.
I'm sure of both dates. LMP 8th march, conception 19th march. She is going by LMP but telling me by the scan I am wrong and it must be later but its not possible. Just concerning me that bubba is not growing as they should be :-(
You are a hundred percent sure of what date, the date of having the sex that produced the baby? Your midwife is saying that your GA (gestational age) is 5 weeks? (Meaning, that you conceived 3 weeks ago?)