23 year old - klinefelter's syndrome?

After doing some research I've have come to believe that I have klinefelter's syndrome.  I originally saw a doctor because I thought I had Marfans syndrome, but upon further investigation, my self diagnosis has changed.  I exhibit many characteristics of Klienfelter's Syndrome i.e. tall, extremely long arms and legs, big hands, big hips, Gynecomastia, mild sexual dysfunction, no chest hair/limited facial hair, high voice.  
However I have a very tall and lanky family and my dad didn't really develop chest/facial hair till later in his 20's. I also have quite larger testicles and penis. I went to a GP and and endocronologist about 1 1/2 year ago and they took my blood and everything, but gave me no definitive answers. Is it possible for me to have had an extra X chromosone, but not show up on the blood tests?  Would the endochronologist be able to make a Klinefelter's diagnosis?

Does it sound like I have Klinefelters? Any advice (other then go to a doctor) I know I should go to a doctor, and I will.  Thanks!

[solace21]

Hi,
    From what I could read from the Net, you may not have Klinefelters, as the main disturbing characteristics of the syndrome is hypogonadism characterised by high levels of pituitary hormones LH and FSH, small genital size, and very low sperm count, all of which appear not to apply in your case. So, I would think your body characteristics  are simply a family trait. As regards gynecomastia, you must have acquired it from your puberty and should get resolved in due course. I hope you take quality food and do moderate exercise. Again, the body hair and facial hair full growth will come normally during twenty-five to thirty years of one's life. You can Google for Puberty and learn more about these.
In any case, if you want to really confirm, as you must have seen from the net, Karyotype blood test to determine the number of chromosomes is to be done in specialised laboratories, many labs would not have this facility.

Solace