If after two weeks you find the beer isn't carbonated, don't fret. Just leave it alone and come back to it in another two weeks or so. I've been home brewing with some girlfriends for almost a year now and we've lost tons of flat beer down the drain thinking we had gone wrong somewhere. It was only after I had left what I thought was a bad growler of beer on the counter for two months and decided it needed to go down the drain did we finally figure out that bottled/growler beer is taking a bit longer than we thought to carbonate. Good luck and I hope it turns out great!