American culture is controlled by huge multinational corporations who therefore are well able to sell it all over the world. So yes you will find McDonald's, Subways, American movies, American brand clothes, etc... all over the world. It does not necessarily mean that 1/ THIS is american culture...
That's a big no with one exception. If the bride picked an unusual colour (not white or ivory) and didn't tell people then it might have accidentally happened.
I can see why you would think you are being judged, but from the description you make it's really hard to guess what these women are all thinking. Personally I believe they're just in awe in front of your ring: specially the ones that bring their friends in to see it. Women just like beautiful...