Your approach planning and execution was poor. You were exceeding the speed limit in a downwind traffic pattern, which means that you were way behind the airplane. Either you were still overwhelmed by the airplane or your reaction time was too slow because you were not correcting in a timely manner to slow the airplane upon entering downwind. Because of your probable inexperience on type you were "leaning" on the A/P and A/T, . . . and the airplane was flying you!
You were cleared for a "close-in" visual approach in which case it would have been prudent for you to have immediately disengaged A/P and A/T and aggressively taken manual control by retarding throttles, lowering the nose, deploying speedbrakes, calling for flaps and gear. But you didn't do that, so the captain did it for you and your ego was bruised.
As a junior F/O with limited experience you should welcome every impromptu opportunity as such to get a real feel of handling the airplane and to become familiar with its maneuvering limitations. In this particular instance you could have accepted a short approach and tight base leg as a challenge and worked with the captain. He obviously had more operational depth than you and he was of the opinion that this landing could still be done, and he did it.
You don't specify the runway length, nor your touchdown point, nor whether stopping the airplane on the pavement was a violent maneuver. There is a lot of maneuvering latitude during a visual approach before it may be classified as "unstable."
Most SOPs stipulate that a stabilized approach in VMC can be as late as 500 feet; 1000 feet in IMC.