It was ONE of the best days ever.
But finding my baby was a little girl, and was healthy, was probably THE best day ever. Another great day was meeting my favourite Hollywood star...
But I have had some other great days in my life... including seeing my favourite music stars in concert (Madonna, Prince, Whitney, and David Bowie, to name just 4.) And on my 40th birthday, I went to a country I had always wanted to visit for the first time ever. 
Also DD's graduation was a fab day.
Been through some tough times (like many others have,) but have had some good times too. 
Back to the OP's question... My wedding day is in the top 5 best days ever... It was a wonderful day.
Small (with only 30 guests,) but still lovely... Me and DH (and DD) look through our wedding album with great fondness!
I do agree with some posters though, that this expectation that your wedding day HAS to be super-wonderful, and the 'best day of your life,' is very stressful for some.
I am really sorry yours wasn't great @Opal93 
Hopefully, everything in your life is fab from now on! 