take the puppy to the vet just to be sure but I think you might of hurt it a little and it depends also on how you dropped him/her and what position he/her landed in
How did the puppy fall? Did it fall far? Did it fall on something soft like its bed? Or on a hard floor? Did it hit its head? Or yelp?
I think by far the safest thing to do is take it to the vet just to be checked over to be on the safe side. No doubt it will be ok, but better safe than sorry.