I need some help with my car not starting, 2003 Legacy GT 2.5

So on my way to class this morning, my car started right up and took off with no problems. Just as I was about to get to campus, I lost power to the engine and my power steering cut out. I hopped out and pushed it to a side street before trying to start it back up. The radio, dash panel, and headlights still worked fine. I remembered that I had left the dome light on all night and thought that maybe it had drained the battery to the point where it had enough charge for on start, but that doesnt make sense as to why it would just start. I had my room mate pick me up and take me to O'Reilly's so I could get another battery, (When I had my oil changed a couple weeks ago, they said my battery was at the end of its life and I should look into getting a new one) If it didnt fix the problem I still needed a new battery anyways. After we threw the battery in and got everything hooked up, I tried starting it again, and it was the same issue. It would sound as if it were going to turn over like usual for a second, but then it went to a lighter, less guttural starting sound. I had half a tank of gas so its not that. Is it the alternator or would that effect the power to the whole car? I thought it could be the fuel filter needing to be replaced and the engine was just starved of fuel. Any ideas?

Edited March 14, 201610 yr by dr.earlfunkton

How long since timing belt was changed??

How long since timing belt was changed??

I havent had the timing belt changed since i've owned it so about 35,000 Miles. Would the mechanics let me know if it needed changed? Cause they didnt.

how long since the timing belt system was serviced?

 

were any warning lights on? any new ones come on?

 

is the CEL on? if so, get the code(s) read and post them.

yeah, timing needs to be checked.

how long since the timing belt system was serviced?

 

were any warning lights on? any new ones come on?

 

is the CEL on? if so, get the code(s) read and post them.

All the lights come on when I turn the key on like normal. the CEL isn't on by its self.

More specifically, how many miles on the timing belt? They are supposed to be changed at about 100,000miles. Over that, you're on borrowed time.