
I say don't worry about it. When I bump mine (or in your case, jostle him during the move to your tank), they pout for days and won't come out of their shell. Your water params look good, so that's likely not the cause.
If Mr. and Mrs. Snail are tucked tightly into their shell, and the trapdoor is pulled tight, then you know they're still alive - it takes muscle tension to keep the trap door shut. Give them a few days, don't mess with them or make waves in the water, and once they feel comfortable, they'll start zooming around like you wouldn't believe a snail could do!
