Finally! I did it! I felt like doing a dance of joy and shouting really loudly, but I held back. The golf course where I do my jogging is pretty quiet at 7:45 in the morning, and I didn't want to disturb any residents or hotel guests. The last 10 days or so, exercise of any kind has been an iffy proposition, as my knee has been bothering me. I don't think I injured it, but it's been painful off and on. Oddly, it doesn't hurt to walk or run, but I've been taking it easy in general to try and allow it to get better.
So, now that I know I can endure 3 miles if I want to and I'm feeling good and the stars are aligned and it's not too hot or too foggy or too humid and I wake up on the right side of the bed... I have 12 weeks before I actually run a 5K race to improve to the point that I can tackle the race with confidence. I'm not expecting to place or anything, I just want to finish. I've been saying for several years that "next year I'm going to run in this race," and it feels really good that this year I'm finally going to be ready to do it!