The answer is "No."
Now, getting married is the second most important decision in your life, make no mistakes about that (choosing your relationship with God is most important), but the day itself isn't that important.
I have been involved in the planning and execution of many, many weddings over the years. In fact, I am currently called "The Church Wedding Organizer" if anyone wants to use the facility for their wedding, though this isn't really an official job, more a way to make sure the church property is used correctly and to help people make decisions than anything.
One thing I have seen:
Weddings seldom go perfectly.
The flowers go to the wrong church (my wedding, actually), the groom can't find a iron to make his uniform look right (military), the bride gets a run in her hose, the mom shows up drunk or mad or both, etc.
Weddings today are big productions and, as with all big productions, what can go wrong will go wrong.
But it doesn't really matter.
A wedding is simply the day marking a life change.So is are births, deaths, and moves.
In the long run, if your wedding is "The Most Important Day in Your Life" you need to change your life.
Much more important days:
the day your life-mate smiles and laughs,the day you share an inside joke,
the days your babies are born,
the day you watch your love playing with your toddlers,
the day you see you love talking with your children like adult friends,
the day you make up from a "disagreement,"
the day you decide to move,
the day your own children get married,
the day you hold your first grandchild,
the day you your second grandchild,
etc,
the day you share the sunset with your love,
the day you kiss in the rain,
the day you realize they have a cold so you decide not to take the snappiness personally,
the day the car breaks down and you decide to have a picnic while waiting for a tow truck,
the day you buy your first house,
the day you sell your first house,
the days your parents die,
the day they remarry,
the day you gather with friends and family for the holidays, or church, or a party, or just 'cause, .....
No, your wedding is not the most important day of your life. Not even close. It's just a day to party with friends and family, and celebrating one of many life-changes you will have in your life.
So if (when) something goes wrong on that day, choose to smile and laugh at it, say "Meh," and go on. It's not nearly as important as days to come; not nearly as important as the marriage is.