late bloomer?

  I am a 17 male that has not developed sexually yet. My penis size has not changed yet. I have grown pubic hair and have had it for a year or so. Normally I would just think I haven't developed yet, but when I was like 8, I suffered a very severe groin injury, I went to the hospital, but left before they could see me because I felt better. I masterbate and I do have an orgasm. I am wondering if there is a way for me to tell if I am going to mature without going to the doctor, as you could imagine, it is pretty embarrasing and I don't know how to tell my parents when they ask me why I want to go to the doctor. HELP!!
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Dear Matt
Your puberty is delayed even though you have started to show pubic hair.  Signs of puberty are fairly predictable.  The testes  enlarge and form more testosterone, male hormone.  A growth spurt ensues and growth in accessory sex organs like penis, prostate  and  seminal vesicles.  Hair distribution ascend up the abdomen chest and underarms.  The voice also deepens.  The musculature of the upper body increase in size.  A lack of some or all of these manifestations may indicate you need medical help.  Delayed puberty usually runs in families.  This might be an ice breaker topic to talk to your parents and to let them know you are concerned.  You do need their consent to go to a doctor  and receive treatment.   Time is important because if medical therapy ( hormone replacement) is needed, you will not waste valuable time for catch up growth.  A sports physical maybe another opportunity to get in to see the doctor.
More individualized urological care is available at the Henry Ford Hospital and its urban campuses by calling  (1 800 653 6568). We can also arrange local accommodations through this number if this is your need. Please bring any physicians