Safari :: Clicking On Red Button (close Page) Opens A New Window

When I try to close safari using the red dot at the top left hand side of the screen instead of the window closing it opens a new blank safari window. Infact the same happens when I click the amber and green buttons also.

I recently have had to system updates (last night and today). Last night I also had a problem that has fixed itself where pressing the command + Q buttons would not clos safari and the "Quit safari" in in the safari drop down was greyed out. As I say the later isue has fixed itself after I force closed and the updates loaded on. Not sure if the two issues are connected.