I wouldn't say I regret it, I have a long ways to go, but sometimes I do wonder tho.
How life would be different...Being a "normal" person...being able to eat what I want, and go without sleep, and drink and party to all hours, and not have any obligations to my body.
And I do regret injuring my shoulder pushing it too hard when I was younger which has never been the same and has halted my gains repetitively.
Other than that, if you are happy with who you are as a person, then there should be no regrets because every moment in your life has shaped you in some way today and without that experience you wouldn't be you.... Be proud of who you are