Bought wrong tickets for warped tour what to do?!?!?

I told my step dad the dates and I said July 14 at canton NJ but I just touchy of it and doubled checked and cantons date is the 28th. what do I doo? I mean is there a way to exchange the tickets and get canton? and it sucks because I was told my dad and his girlfriend and family are going on vacation the week of the 14th and idk I'm soo stressed idk what to doo!!