I am 51 and if I were 25 again, there are certainly SOME things I would do differently. Having said that, I am grateful for the life I have had, do have and will have going forward. It's easy to look back and say "I should have done so and so" but the fact of the matter is you did not do that and instead did something else. I choose not to dwell on the things I would do differently now. Besides all that, there might be some things that had you done them, they might not have worked out the way you think they would have.