My baby's head measures 2 weeks ahead..does that mean i'm farther along?

Okay, I'm not tellling you this to scare you, just to give you as much info as I know. Sometimes in cases of I.U.G.R. (intra uterine growth restriction) when the baby is not getting enough nutrition to grow properly the body will divert more resources to brain development, resulting in a head that is disproportionately big compared to the rest of the body. Since your baby's femur is measuring correct and not small for weeks it may not be anything, but if I were you I'd bring this up with your doctor just to be on the safe side. Also, ultra sound measurements are not exact, just estimates and also subject to human errors, so maybe that's the case. In regards to your question about your baby being big, I don't think that's case if the femur measured normally, plus within 2 weeks is still normal and is probably just due to the margin of error on an ultrasound.