Well, if that happens again, try hitting stop and then refresh. If the page then loads quickly, then here's the reason:
That happens sometimes because routers in the internet are trying new routes to places, and you just happened to hit a snag. If that happens more often like you are describing, let me ask you this: has there been a thunderstorm, earthquake, or power failure recently in your area, if there has, that may have knocked out some of the lines and the routers have to find new routes.
In retrospect, there's not much you can really do about it except so stop & refresh when it happens.