Okay, so let’s say God is watching you walk along.
Walking is a good thing, nothing wrong or sinful about it, and God does will that we should be able to walk around, yay!
Now, let’s say God gives you a little nudge or whisper: “Evangelize those guys!” God is not telling you to stop sinning and start doing something good, because you weren’t sinning to start out with. He is calling you to stop doing something good and start doing another something good. (In this case, evangelization is a higher good than walking.)
When you are presented with a choice between two good things, you use prudence to choose between them. (And in this case, maybe you need courage too.) So you exercise a virtue (or two). Either way you choose, you are still going to do a good thing, although choosing the higher thing may strengthen your virtues.
In this case, you chose to evangelize, and then you ended up doing a less formal kind of evangelization than you had originally planned. You exercised prudence, even if you were not able to carry out your choice as you’d planned; and you exercised a little courage, even if not as much as you’d planned.
In general, you did a good job, and a good deed. Execution may have been a little sloppy, but practice makes perfect. Good for you!