Dying battery

Good evening!
I’m new here. (David)
I own my 16 Civic Coup 2.0 Cvt Automatic Transmission. I unplugged my MAF sensor to check it. I failed to plug it back it back up and cranked the car up-creating a CEL light, EPS, TPS, light. I disconnected my neg cable to try and reset the light but it sparked a little. When I tried to re-crank it, I noticed the alternator isn’t charging. There is a battery temp sensor on the neg post. Could I have blown this? I know my alternator isn’t putting out 14 volts, it’s only reflecting 12.20 as is the battery surface charge when the car is off. The battery will not turn over.