I need help with Pokemon Platinum?

Okay so I just got done beating the snow point city gym, and I went to the lake close to there (forgot the name) I know I have to go to veilstone city and beat team galactica, but how? I accidently already went in the wear house and looker went ahead of me and whatever, but that was waaay before I beat the snow point city chick... So did I screw up the whole game? WHAT DO I DO NOW?!?!?!?!