2001 Toyota Corolla Jumpstarts, runs, turn off, cannot rest

I am probably answering my own question pertaining to this but I have a 2001 Corolla in which i have had no problems like this for the entire 7 years I have had the car. I drove to a coworkers house the other morning with no problems, parked it, carpooled to work, came back that night, and the car was dead. Jumpstarted it right up, drove to a gas station to pick up some foodstuffs, and again would not start. Had to get car jumpstarted again to get it home, ran it in the garage (with the door open) for at least 5 mins. Turned car off and again would not restart. attempted to use a battery charger to charge the battery and was getting two messages: 1) stated charging went only up to 1.9A. 2) unit stated Alternator voltage bad.... as i said im probably answering my own question and as of right now i have not tried to restart it for 4 hrs. The battery is less than a year old... If I had to take a shot in the dark id guess the Alternator needs to be replaced.

Thanks