Are you sure it wasn't a static electric shock, rather than AC? If you live in a dry climate, or in a cold climate without a humidifier, and you may have walked across a carpet, it could have been a spark of static electricity. Especially if it hasn't reoccured.
If you buy a similar model from the same manufacturer, you can leave the sink fittings in place. Unplug the power and disconnect the waste pipe. Undo the bayonet fitting securing the waste disposal unit to the sink fitting. Fit new unit to sink fitting, reconnect waste pipe and power. Run the unit with plenty of water to check for leaks. Job done.
TURN OFF POWER before sticking your hand in.!!
But first check the reset button underneath the unit. Also, try to rotate the spinner with hex key usually provided.
Drink beer and then recycle glass bottle or aluminum can
Then research recycling route for all recycled and non-recycled waste products If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7
The two drains are connected, but below the disposal. Likely if it's not draining down, you still have a clog, and the person the "cleared" the drain didn't.
Sometimes the disposal rotor is jammed by a piece of chicken bone for example. You can use the supplied hex key to stick into a hole at the bottom and jiggle the rotor free.
Check on the bottom of the unit, the shaft usually goes all the way through and on the bottom has a socket you can put an allen wrench in to twist it. IF that is not the case, you can use a wooden broom handle through the opening in the sink as a lever to break loose any jams
The one thing they don't tell you in the instruction guide is how to hold the garbage disposal in place while attempting to connect it to the drain collar.
After trying to lift, balance, and align the disposal to the point my arm was getting warn out it finally occurred to me that there was definitely an easier way. I went down to my car and got my scissors jack, put the disposal on the jack, and slowly eased it into place until it mated with the drain collar. Easy as pie from there on.
On the very bottom of the disposal there is a small opening in the very middle of the disposal. If you shine a light under the sink and put a mirror down on the inside of the cabinet you should be able to see this. You'll need an Allen wrench to put in the 6 sided hex hole and turn counter clockwise until the disposal turns freely. This should unjam your disposal. Don't forget you may have to hit the small reset button on the bottom too.