Umm im pretty sure putting the half an amp into the analog pin is probably what killed it. In the future for testing pins, try going from 5v to 1 leg of a pot, middle leg to the analog, and last leg to ground. It should make a voltage divider that will let you show the full range, 0-1023 of the analog pin when you turn the pot, and it won't kill the pin, (might damage it if you put the pot @ 0 and have the full current going into the pin though, should probably put identical resistors in series with the gnd and 5v legs. I use ruggeduino now because i know how often i break stuff)