It sounds as if you have bent part of the governor, which is a tin plate with a spring and link on it, mounted on top of the carburetor. Most times when this happens it is just the tin mounting plate that is bent, but usually that makes it run slowly, so you may have bent something else. A picture should clarify it. From your description the linkage is simply jammed between where the speed control cable (bowden cable) attaches to the moving link, and the throttle butterfly lever where it comes out of the top of the carburetor. I suggest you give us a picture rather than bending things though - six faults are harder to fix than one.
