With the springs, keepers and locks off and some valve grinding compound You can tell by listening and feel if the valves are contacting the seats all the way around . Also with them dry open and close each 1 at a time ,,,,,,,,,when You're closing them there is a distinct sound the valve and seat make when they contact each other,,,,,,,,,,,You can tell ,,,,,,,,,I seriously doubt You bent any valves as the valves are very strong and to bend 1 or all of them there would be significant damage to the pistons ,,,,,,,,,,,,much more than a small nick ,,,,,,,,,,,You got lucky it sounds
Spin each valve in it's guide and You'll see any bend even the smallest bend You'll be able to see when You spin it ,,,,,,,,,,,,spin it not seated and with lub in the guide .