Am I an idiot?

I just walked away from what might have been a really great job opportunity. I dropped a resume off at a really top notch school on Friday and was immediately interviewed by both principals. The principal called me at home today and left a message asking if I would come in and sub in the classroom I would be teaching in to see if I felt comfortable taking over the classes for the rest of the semester (as the actual teacher).
I just left a voice message and e-mailed him back stating that I did not feel the job was the best fit for me. And now I am wondering am I an idiot? Yes, I am taking a poll, feel free to comment!
The job would have been working with some really fantastic teachers, a really positive and supportive administration and faculty, and some of the brightest and best kids in this county.
But then there are some other issues at hand. The kids were all either 10th graders or seniors in high school, and I just feel more comfortable with middle schoolers. The commute (including dropping my kids off at my Mom's) would have added two hours to my day. I have some nagging health issues that need to be resolved (since it seems my normal life is almost overwhelming me right now), and then there is my stepdad's health. I don't want to burden my Mom with taking care of my kids when her first priority should be her husband, and I know she would never be able to say, "No, I really can't do this." And then there is the idea of being away from my kids 40 plus hours a week, having to work on school stuff even when I am at home, and dragging them out of bed at 5:45 in the morning.
So maybe I am a little bit of an idiot. The money would have been nice, the experience would have been great, and who knows when such a good opportunity will come along again. But the thing I do know, is that the opportunity to be with my kids when they are exactly at these ages and stages will NEVER come along again. That is a certainty.