Replaced a receptical with a switch and wired in a small led light for a cabinet now the breaker keeps popping off

Ummmm, No.

The receptacle is for the full utility power. Do not know what country you are in, but;

USA = 120 Volts (At 60 Hertz)
Europe = 220 Volts (At 50Hertz)
Australia = 220 Volts (At 50 Hertz)
Japan = 100 Volts. (Generally)

Now you connected a small LED light, connected to a switch, that power usage is rated at probably 100 Milli Amps.
That would use less than 1 Volt.

Regards,
joecoolvette

replaced a receptical with a switch

Well, that doesn't tell us much. You have to tell us how you wired the switch.