Were the lanes set up the LONG way (length) of pool and the the "width" of the pool? Then it is 50 meters (one length)--as that is how most competetion pools are set up.

I did my first tri...my swim time was almost 15 minutes for 1/4 mile.
I know when I timed myself in the pool I did 400 yds in a little over 13 min.
I am slow. But steady. And thus room for improvement!