Don't quit man! I started playing competitively really late too, I didn't play in the highest level of tournaments in my section until I was 15, and I did not do well at all.
I'm now at a D3 school and it's perfect for me. Some D3 teams are still really competitive and it's just not as stressful as being on a D1 team, plus I know I can focus on getting solid grades at a great academic institution.
Wilson BLX Blade 98 strung with Solinco Tour Bite 16 at 52 lbs. My College Tennis Video: http://www.youtube.com/watch?v=2SfqRalc0V8