What if it was defective and didn't work, before you dropped it? Most electronics is not tested before it is shipped.
On a positive note, if it is under warranty then go ahead and swap it out. It will give you some peace of mind.
Working decades ago in computer stores: yes, some times the boxed computers fall from the "high steel" when boss wants a floor display. And if it doesn't dent in the corner of the box, noone will know. No customers ever returned a computer because it didn't work as expected.