Maybe generalize your goals a bit more? Maybe you didn't anticipate running a mile in under 12 minutes, but I'm sure you were trying to go faster...so why not something like "improve my running speed" or "better endurance?" That way you're giving yourself guidelines that you can hold yourself accountable with, but the degree to which you do so is entirely up to you. Bonus: if you don't have specific numbers, it can be a continuous goal until you're satisfied with a final result. If you find you're doing better than anticipated, it becomes a continuous challenge to see how far you can go.
I have a list of specific mini goals, but if I didn't already have them in mind, this would probably be the way I'd go.