It is not unusual to hit a plateau presolo when you get to the circuit. One of the causes is insufficient time spent on the fundamental flying skills of holding the rich attitude for the desired flight condition and/or insufficient emphasis on trimming the aircraft. Too many instructors rush their students to the circuit and then spend many frustrating hours making no progress, The circuit is not the place to learn ex 5-9.
One strategy I have used successfully is instead of starting a lesson right into the circuit,I go to the practice area and practice flying a circuit at altitude ( ie the runway is North at 2000 feet AGL and the circuit is at 3000 feet). This lets you practice the rhythm of the circuit without the pressure of the runway looming in the windshield. Concentrate on flying "finals" on speed with a stable pitch attitude and in trim. Now when you go back to the circuit you will be warmed up and ready to go
. It is also a good exercise as it makes you practice a go around.