If you knew then what you know now... Hindsight is 20/20... Maturity is knowing what you don't know... it goes on and on. Seriously, would it have made any difference? If you look back on your life, are there things you would have done differently? Do you thing that by doing things in an alternate way you would still have the people in your life that you have now? Would you really be able to say things would be different - or just a slightly different version of where you are now?
I think there is something to be said about the old cliche "things happen for a reason." I hear that line said over and over and what I really want to say in reply is "Yup. It happened because X happened, then Y happened." Life is a continuum of events. Some events are positive. Some events are less positive, but they are indeed just events. They have been following each other since the day we arrived on the earth. This is likely the most important thing we can take from life... shit happens, and it follows other shit, and will indeed be followed up by more. Life is the stuff that happens while we are busy 'would of, should of, could of' ing our lives away. Does it happen TO us? Nope. It just happens. So for today - and even if it is only for today there should be no would of, should of, could of. Today is Toss Away the Could Haves and Should Haves Day.
Honestly, even if you do pull a would have should have could have today, you can just say you shouldn't have. I'm not sure how to celebrate this one other than just enjoying the day and all life has brought you. Regret nothing. Without the mistakes you may have made, you wouldn't be who you are today. And since is is also National Daiquiri Day, at the very least you can sit on a patio somewhere and enjoy a drink. If you imbibe in a few, don't worry about it. Should you have had all those daiquiris. Probably. Would you regret it? Not today. Could you have ordered a soda? Sure. But would you wish you had had that drink tomorrow? Who knows. That's tomorrow. Live today. If you try and live for tomorrow you will miss the moment you are given right now. You can go ahead and worry about today tomorrow.