Most Helpful Guy
I had Runner's Knee in high school, though the term is used so broadly nowadays that the condition isn't always the same. In my particular instance, I had a muscle imbalance (strong hamstrings from distance running, weak quads from a lack of sprinting/strength training). So when I finished a race, my hamstrings would be tight (tighter as I rested my legs), problem being my opposing muscle-- my quads which are responsible for holding the knee in place-- were not strong enough to counter this, causing misalignment and off-tracking when I bent my knee and as a result pain strong enough to keep me from being able to walk post-race. The problem was temporary and only came after running, except a clicking in my knee that came every other step when I walked (for like a year cause I never treated it until I finished my last year of cross country)..
The solution-- heavy weight squats. The clicking went away, the post race pain (incapability to walk up steps) went away and no running injuries since.
Runner's knee is not an injury that is permanent and one more race shouldn't destroy you. But now that you're aware, start strengthening your quads since strong quads = strong knees. In 2 months of strength training (3-10 sets of 3-10 reps weighted squats), you shouldn't have any knee problems. If you do, check your running form, feet pronation and give running a rest. Otherwise, you shouldn't need to stop running-- just more cross training. I kept running as I recovered from my muscle imbalance. Make sure you're eating enough, resting enough for muscle recovery too. And good luck, hope this helps.