Did you just jump in the pool/ocean with your AW without any further protection? I knew it could tackle a shower, but thats pretty impressive!
A few links for further info on water resistance:
http://www.dcrainmaker.com/2015/05/apple-watch-waterproofing.html
http://furbo.org/2015/07/14/a-watch-water-and-workouts/
Like ALL watches, if you go into chlorine pools and ocean, then you need to rinse it good afterwards.