You did the right thing by racking them. Although it probably would've been ok until it was finished fermenting. From you SG reading you're getting close anyways though. Since nothing is perfectly tight the co2 would eventually be partially supplanted by some surrounding air. As long as fermentation is in progress it generates positive pressure in the carboy. Other than the loss of volume there isn't any other harm in racking. Just make sure to leave as little headspace as possible while leaving enough so if the jug gets warmed up for some reason it won't overflow through the airlock when it expands. I like to make my batches of wine/mead cool and slow. Primary fermentation for a week or two and then racked every three months for a year and then in the bottle for another year of storage(if I'm patient enough). Let us know how it comes out
