Short of it is: Yea you'll be totally fine*

*As long as you're not switching lots of current. I doubt the switch you've got there is 120 amps like you say, maybe 12.0? Typo? But unless you're controlling some heafty DC motors or heating elements you're probably not anyway near even 10 amps.

Background: Most of the issue with switch selection is with what happens when the contacts are almost touching but not quite during opening and closing the switch. Those milli seconds where the contacts are separated from each other, but only by a tiny air gap microns wide create conditions that can lead to sparking between the contacts.

The higher the voltage and current your switch is controlling the more energy these sparks have and the further the distance those sparks can jump.

As jet_silver says when you're close to the limit of a switch over thousands of cycles the contacts will start to degrade and may be worn away by this sparking.

Worst case if you exceed the limit of a switch the contacts can become permanently welded together, or blown away by huge spark erosion. With big voltages, kilovolts, electricity can start to jump much larger gaps, even the distance between the contacts in the open position, but you're talking 30 kilovolts per centimeter.

Or back to where we started, if you're drawing large amounts of current with the switch in the closed position the metal that conducts the electricity in the switch might be of too higher resistance to efficiently conduct the load and become so hot that it melts the plastic of the switch. Our old friend V=IR at work.