I served in the military so no regrets there. It was an experience that would probably be good for most folks to have had. I never had even a remote desire to make it a career.
I did a lot of construction work in the summers before I went in and always enjoyed designing and building things. After i got out I tried several things and took a job at a small engineering company my Dad worked at after his construction company went bankrupt. (During the Carter administration I believe that home loans were going for about 18% interest if you can remember or imagine that. So not many people were building houses.)
I started with that company making $3 an hour running errands, running blueprints and scrubbing (Making corrections to) engineering drawings. That was about 40 years ago. Now I am a Civil Design Project Leader for a large utility company and make as much salary and have as much responsibility as folks with Bachelor and Master's degrees in Civil Engineering.
I do regret that I never finished my Civil Engineering degree. But I can't complain, I love my job, I love what I do, I love the people that I work with, I even love my company (Although I still bitch about it sometimes

) they have been very good to me. I love the feeling of accomplishment and pride that comes with daily tackling a complex problem, designing a solution, working out all the details, managing the project, seeing it come to fruition, and finally being there when it's all built and working like it should. I'm constantly faced with new challenges everyday, and I love that stuff. It keeps my mind sharp.
I think a lot about whatever you do is attitude. I remember my first job... Pumping gas at the Citgo in Cahaba Heights. I had my blue shirt with my name sewn on it, and I would go out there, talk to those Mountain Brook women, fill up their tank, check the oil and transmission fluid, wash their windshield (getting all the bugs off) and check their tires. I was probably one of the best gas jockeys you have ever seen. Even though I was pumping gas I took pride in what I did, and I still do that today almost 50 years later.