I'm 33 weeks& just had an ultra sound todaythe doctor said the ultra sound lookd normal except long femur& hemur, short parents, no other markers

Long femur. The femur is the bone of the thigh. Though there are indications that a very short femur (less than 5th percentile) is associated with chromosomal problems I have not heard of longer bone lengths found on an OB ultrasound being a marker for any problem. Likely this is your baby's genetics. And a long leg bone a birth doesn't mean your baby will be tall.