Alternator? Battery? Please help!
 

Ok, you guys are gonna think I'm crazy, but maybe this has happened to someone else. I have a 99 grand prix with around 172,000 miles. The car has been running great until I stopped the other day to get gas. I shut it off, fueled up, and then tried to crank it back and it acted like it had a dead battery. So I got jumped off and it ran real rugged for about a mile till I had to stop at a red light. Died again. Got jumped again. Ran rough again a couple of miles, got pulled out in front of, died AGAIN. Got jumped AGAIN. Then the car wouldn't stay running once you took the jumper cables off. I heard from multiple people "it's the alternator" so I took it off and took it to autozone to get tested. It PASSED. So I took it back home and put it back on the car, jumped it off and it stayed running!?! Drove it to the store and back and it ran smooth. Now the battery light comes on while idling, but if you rev it up it goes off for about 10 seconds then comes back on. Is it a bad alternator? Is it a bad battery? Am I CRAZY? PLEASE HELP!