Is it 'bad' for a guest to wear the wedding colors to the wedding?

I'm attending my friend's wedding in the middle of July, since its a formal, outdoor, day wedding and I am all of 5' tall and a little on the thick side (street size 12), I've been searching for a dress for months. I finally found one 3 days ago. A very pretty black dress with white and hot pink polka dots that has a bit of a 60's look to it. Trust me, its more formal that what it sounds. I get it home and show it to my fiance who looks at me and says "Um, is it okay to wear the wedding colors to the wedding?" I was so excited about the dress that I didn't even notice its the same as the wedding colors. Is it okay to wear, or do I need to begin my hunt again?