I am positive that my newly created world did not produce a nether fortress.

My cousin and I put in at least 10 hours into this new world over the last few days and we really don't want to make a new one. It is for the xbox 360, which is completely updated to the current date of 7/22/2014. The seed number is -537036197629107152. We searched far and wide around all the lava pools, corner to corner, I've reset the nether multiple times and we get nothing. Any ideas on how to generate one?