That's more like it, as Millsy suggested why not post your exercise/running routine and I'm sure all the helpful people on here will help you with tips as to how to improve. If you do it right, you will definitely improve. Some recent race times would help too.
Hi Kat. You'll certainly get a more informed opinion than mine from someone else but to me it sounds like you are over thinking and complicating this. Be pleased with being fit and healthy! If I were you, forget this and if you haven't before then get yourself a proper training plan. As you improve your running fitness your times will start coming down. Have you done a 10k before and if so what was the time? Smart training is the key, you'll get there and beyond so long as you train right. Keep up the good work!