Try not to have too many regrets in life. Can't chance what's been, only what is and what's to come.
Only two things I'd change are giving myself a kick up the arse to get in shape ten years go instead of five, now I'm forty and everything just gets a little more annoying to accomplish with fitness.
Second would be to have not gone on the car trip that resulted in someone apparently not seeing the queue of cars behind us and just not breaking, resulting in periodic lower back pain for me and 6 months of my eldest daughter being very cagey about being in cars.