Ford Contour GL. Need help ASAP!

Hi,

I am the owner of a 1998 Ford Contour GL, automatic trasmission. I just had to get a new battery installed the day after Thanksgiving. However, last Wendsday, as I was driving to work, my battery light started flickering. It didn't stay on, it just kind of fizzled on and off then it stopped. Yesterday, 1/7, the battery light came on and stayed on. This morning, 1/8 as I was driving to work, I noticed that the lights in my console were dull. I also noticed when I went to clean my windshield my wipers where moving slow as well. As I continued to drive, everything in my cobsole started to go completely dark. My ABS light came on and the air bag light was flashing. After being stopped at a light, I started taking off and the car was crawling. By the time I got to work, the radio did not work, and if it did come on you could hear nothing and I got out and looked at my headlights, and they were dull as well. I turned my car off and tried to start it again and it wouldn't. I just get this clicking noise.

I know that the altenator gives power to the battery and I think this may be what it is but I am not sure. Is this it, and if so, how much does something like this cost? I don't have a lot of money so I am worried that I will not be able to get this fixed.