9 minutes is an awesome pace. I have friends who've been running for years who haven't hit that. (took me a few years myself, though I can now do sub-7:30.)
good luck with the 5K!
For future running, I find it easier to increase speed and/or distance one at a time, and not try to increase both at once. So if you're trying to build distance, do it at a comfortable pace, and then once you have the distance, start whittling away at your pace, at the distance you've mastered. Or get comfortable at a faster pace and then take the distance up. Either approach can work.
