No,as long as it stays sealed it'll be fine. Are you using a hydrometer to make sure the beer's were done fermenting? The airlock bubbles usually slow down or stop only when initial fermentation is done. It then slowly,uneventfully ferments down to FG. Then allow another 3-7 days for it to clean up by products of fermentation & settle out clear or slightly misty. There are many times in my brews when 3 weeks are needed to finish fermenting & settle out.