I bottled a Cooper's Irish Stout batch, 3 weeks ago, today. It tastes great, and is a bit "stouter tasting" than either Guinness or Murphy's, which is a plus for all of us. The problem is that it has very little head or carbonation, at all. I used 2 priming drops per 750ml bottle as instructed (I used a Cooper's kit and the package and followed all of their instructions). Where did I go wrong with the head? Does it need more bottle conditioning time, or will it develop any more head? I really like the taste, but it is just a bit flat...