non, DV are pretty sturdy. I dropped a few too, sloppy me
Unless you dunk them in coffee or run a tank over them, they should work fine.
I'd shake 'em a little and try winding them slowly in a tape rewinder to check the mechanics are working.
Remember when cassette tapes were in? I broke a few in my time and even managed to move the tape from one cassette housing to another, because I didn't want to lose the music on it!
Either way, be sure to capture or copy your shoot masters right away.
Proper backups applies to tapes as much as it does to data on a hard drive.
And yeah, DV tapes are preaty sturdy - and the (cheap brittle) cases normally break long before the tapes do. The better cases don't break, but they protect the tapes even more.