Well there could be several factors, if you poured it in several glasses then the small amount of beer allowed the sulfur to dissipate before you drank it. The atmosphere wasnt ideal for judging beer. The yeast cleaned up a little bit during conditioning bringing the sulfur below detectable thresholds. Bottle variability? Have you tried another bottle at home in a good setting?
The beer seems to be fine now. The first one I had was after 5 days of bottle conditioning. That is when I had the sulfur smell. Now the beer is conditioned 2 weeks and there is no more sulfur smell.
You only cracked one? Then you lost the Russian Roulette and cracked a bad one, most likely. About one in 50 bottles goes nasty on me, and it's usually the one I give to someone right before I tell them how great it is.
