If waiting doesn't help, try logging in to the account in a different browser, if available, or disable any browser add-ons, etc, that might cause an issue.
Alternately, try opening a new private browsing session to test (unless this was moved in recent updates, Opera has a 'New Private Window' entry in the main menu [Ctrl+Shift+N], and Firefox has the same in the menu [Ctrl+Shift+P]).

Quitting the browser and restarting may help, or at least close any other tabs open to that site (if you opened the verification link in a different tab/window, etc).