Clearing your browser cache is like restarting a computer or your phone, it can eliminate an amazing range of problems, especially the kind that only your browser is showing, but no one else's is.  It's always worth trying at first.

If you don't know how to clear your Browser Cache, this is a helpful tutorial that explains the process for many different browsers (with pictures!): Clear Your Browser Cache

Note: Just remember, if you're on Firefox or Chrome, to select only "clear browser cache" otherwise you'll lose your browsing history and any saved logins/passwords. (which can be rather annoying!)