Short femur length

Just did growth scan at wk 30. Doctor said head and tummy size are good but femur length is short. Had done Harmony test and FTS and results for both are low risk for Down Syndrome. Doctor mentioned short femur length is probably constitutional and can cause baby to have fractures easily in future and also risk of dwarfism. Freaking me out. Scheduled for another growth scan in a month time. Appreciate anyone who has similar experience on this for advice.#pleasehelp #advicepls #1stimemom