Re: Is it my alternator?
Sounds like a faulty battery ground cable to me, since you tried jumping it and that didn't work.
Measure across the battery terminals, 11.9 to 12.5 would be a good reading, if you see that then
try connecting one of the black jumper clamps to the engine and the other black clamp to the negative battery terminal.
If that gets it running, you should be seeing somewhere between 13.8 - 14.2 volts between the battery terminals, this would indicate that the alternator is working.
Time to clean the negative cable connection to the fender.