Welcome to HBT, we're glad you're here!
I'm not familiar with your setup but I know there are a couple of folks that use the Brew buddy so hopefully they can answer your questions. You must have a leak and my uneducated guess is it's around the lid. Maybe some lube would get you a better seal. How disappointing that you had flat beer on your first brew. Good luck having your next beer nice and bubbly!
BTW, just to give you a little razzing, not all of us are lads.