17 year old with prostate concerns.

Hello I am 17 years old and a couple months or so ago I had a bit of a revolutionary idea that I should probably start drinking more water during the day. So I began to consume four or five glasses of water per day, and naturally my average time in the bathroom slightly increased. Now, about a month ago I began going to the bathroom at an even increased rate. I also felt that there was still just a tiny bit left after I was finished. That tiny bit ended up as drops that would accumulate in my underwear. Still didn't really think much of it. So about a week ago I had my annual check up. No bacteria or blood was in my urine, so I am clear there. But my doctor said I might have an enlarged prostate which is incredibly rare for someone my age. He told me to wait for more serious symptoms but ever since that day I've been thinking about it much more, and consequently spending more time "feeling" the urge to pee. I don't have this annoyance when I'm sitting or swimming. I notice much more when I am up and walking around. Is it very likely that I have an enlarged prostate? I have no other symptoms. My doctor suggested it could be my hormones, since I am still in my pubescent stage. Thank you for any answers!