If I had a time machine, I would probably go back in time and just live it all over again. There are distinct points in time that I can change and become a different man, but it is doubtful if I would want to become a different man. My regrets are very silly like deciding to watch a movie next week but the movie changes before I watch it.
Something I feel very guilty till date is something that happened at Malampuzha when I was a kid. Dad got my little sister and me hydrogen balloons. It was tied to our hands. She found hers little loose and came to 5-6 year old big brother to tighten it and I did. But I actually made it worse and it flew off from her hand. I did not offer her my balloon. I still live with that guilt. If anything, I would go back in time and give her my balloon or let Dad tie the string tightly so that we both would have had balloons.