rectangular pool - sides look like they are caving in

Okay.. I'm setting up a 12x24x52 intex pool. The directions and several reviews warn about the long sides looking like they are going to cave in. They say it will be fine but how much is too much? I've been filling the pool slowly over the last week. I'm worried because the the pool is about 2/3rds full but the sides are still warped in. Should I keep adding water and hope the side push out? Or stop? I would attach a picture but I can't seem to figure out how to do that on here. Any advise would be appreciated.

Thanks...

You can either use Picasa, Flickr, Photobucket, etc. or email them to poolforum@gmail.com and reference the URL of this thread.

Thanks .. I've emailed a picture... it doesn't look as bad this morning as it did yesterday...