assuming/hoping you have a good/decent coach, just let the natural progression (physically) take its course and be glad youre not a woman. if you stay healthy and dont drink like an idiot you should get better every year just by doing the same stuff.
that brings us to the next part. mental. it took me about 3 years in college to actually learn how to race. hint, it is nothing about "getting psyched up." it is only about concentration. physically you are much better than a 29xx whatever you said you ran. your problem is you cant concentrate for that long. ill be you do much better in practice than in meets? because you get a mental break. work on being able to concentrate on the race.
i recommend 3k because it is shorter and less time, but depending on your team, they might need you at 5k. if you are running 5k indoors, be careful to avoid injury. it is a lot of pounding on a very hard surface. try to run on grass/outdoor track as much as possible on easy days. also, dont do all workouts going the same way on the track indoors. 200m tracks do very different things to you physically than 400m tracks outside.
good luck!