My biggest regret is not recognizing and enjoying the best time of my life as it was happening. To look back in hindsight and then realize that the best time of my life has already passed it quite. Very few people have died wishing they worked more. The guilt you're feeling may end up being a valid regret though, so maybe work on that. Don't feel bad for seizing moments to relax in a.
I've got two (similar) regrets:
The Brynn Woods Leak: A Conspiracy Bigger Than You Think
Carly Jane: The Aftermath Of Infamy
MyahJanesVIP: The Truth Will Blow Your Mind