Hi,
Do not worry, facial and body hairs are the last ones to come during pubertal development.Have a look at the following link which gives timed sequence of typical pubertal development:
http://en.wikipedia.org/wiki/Puberty
In your case, the onset of puberty is little delayed, to that extent, its completion also will be delayed.In any case, for your peace of mind,it is a good idea to have your hormone levels assessed by an endocrinologist. Do not feel shy in taking to your father and he would get it organised.Also, do take balanced food and do moderate exrecise. You should be ok.
Solace
I would not be too worried at all. Think how lucky you are that you dont have to shave yet because that is a pain I can tell you.
If you are ejaculating then you are obviously healthy and gaining erections.
You did not mention, do you have armpit hair? And how much.
First you should talk to your father, I understand you fell uncomfortable but believe me he will listen. It can be genetic. I know grown men that don't have even peach fuzz on the face.
You said you think your penis and testicles are not fully grown. you didn't state the size of your penis but the average size is between 3-4 inches from tip to base (8.5cm and 10.5cm)
with an erection 6-7 inches (15cm and 18cm) as for your testicles are they descended and in your Scrotum?