Just tight that piece that doesn't allow the door to pass a 60 degree angle... (sorry I don't know how to call that particular piece)
That happened to me once... the door constantly made a loud popping noise when opening and closing it and all I did was to tight the nuts (2 of 'em) that secure that piece. If you open up the door it's right below the air vents, it's the only 'outcast' hinge visible that kinda connects the door to the car. If that doesn't work you might want to tight the door bolts itself (if it was windy enough it could've "pulled-dislocated" the door)