It's kind of a long story behind the mix up. I previously moved, so the invitation never arrived at my new house. I confirmed I was coming, but since I never got the actual invitation, I asked one of my friends, a groomsmen, what time it started. Obviously I should've asked the bride or groom. I slipped in the back row and they never knew. I was too embarrassed to tell them the truth. I did bring a present though.