Time machine

Hi guys, I'm new to the forum and Mac.

back in March/09 I bought my first macpro 2008 model and added a 1tb for my time machine backup which I love it but I noticed last night that my available memory in time machine is is not more left. If I can remembered it says used 453. and available 43.3. What am I doing wrong. I do turn my TM everytime I turn my macpro. Any suggestion you guys can give me will be appriciated.

Is Time Machine still backing up successfully?
Not sure about the figures of how much space used/left if you remember, but you are not sure.
As for no space left, when time machine backup is full, it removes the oldest information to make room for the newest backups.
If you have Time Machine set up to perform automatic backups, then I see no reason why it wouldn't be full.