17 and my genitals are the same since I was 13

Hello, So here's my concern and circumstances. I just turned 17. I am a healthy 17 year old male and a junior in high school. I have been developing facial hair, however more around the neck and not much around my face. I am 5'11 and have been this way since I was 14 my freshman year. I have pubic hair, however I've shaved it 6 months ago and it is slow to grow back. My voice rarely cracks now, and is deep. I've leaned out over time, and I've been keeping an eye on what I eat and my intake of nutrients. I do take a weight lifting class at school, and I've been developing muscle mass. Now then, I think I started puberty back when I was 13, because I noticed the growth of hair in my armpits and pubic area. So my assumption is that at 17, I feel that I am reaching the end of puberty based on what I listed above, with my voice, height, body hair, and other factors. However, my genitals have not grown at all since then, neither in the dimensions of my penis or the size of my testicles. I've been conducting research as to why I am growing in most areas except for my reproductive organs. I do not have a micropenis, however it is about an inch and a half flaccid and 4 inches erect, so I know that it is smaller than average. Sometimes it is buried when flaccid. So here's my questions... 1. Is this a hormone deficiency? Namely, testosterone? 2. Is it merely a matter of genetics? 3. Am I still in puberty? If so, how long might it last? Will my reproductive organs grow in that time? 4. Is this the size I will live with for the rest of my life? 5. Do certain activities stunt growth? Like masturbation or weight lifting? I understand puberty varies in person to person, with genetics playing a major role in how the human body develops. For me, the size of my penis might not be a physical health issue but it's more of a mental/psychological factor. I fear that it may influence future relationships and prevent me from being able to procreate and have children. Thanks for understanding where I'm coming from and thanks in advance to anyone who can answer my questions. And to anyone out there going through this like me, you're not alone, apparently. Thank you