Aww... well I suppose its
Aww... well I suppose its best to wait 'till your all healed up. But when it does come time to race, or even during your training, just tell Mr. Ego that you'll actually go a lot faster if you focus on being comfortable rather than just going fast. Once your form is all locked and you aren't using any more energy than you need to, you can just fly. But if you try to push it and just go fast, you will end up being very slow, very tired, very uncomfortable, and very unhappy.
I also agree with Matt, thats pretty much how I ran my 5k's even in Cross-Country, take it kinda easy in the first mile, then when you've figured out who's actually slower than you, start passing. Just lock on to the closest person in front of you and slowly draw them in. It may seem like you'd end up farther back then if you just stayed up front, but I've had races where there are about 30 people ahead of me at the first mile, and I've come back to finish 5th.