If your sexual organs are too
short it can be due to testosterone
deficiency, pituitary hormone deficiency, hypergonadotropic hypogonadism and growth hormone deficiency.Various investigations required are chromosomal studies,hormone studies like Gonadotropins (LH and FSH), Testosterone and DHT levels,thyroid hormone lvels,ultrasonography and testosterone therapy.
I would suggest you to consult a urologist and discuss this possibility with him
I hope that helps.Take care and regards.