As others have said: don't worry, you will get the hang of it.
One piece of advise: it often helps to do the following exercise a few times:
Fly the approach as normal, but when you would normally throttle off and touch down, don't. You are not allowed to touch the runway, you should fly 1-3 feet above it. Touch the runway and you loose. When you are approx halfway the runway, throttle up and go around.
I did this a few times when I had the same issue as you do. It helped me a lot in getting the feel of control on the airplane.
Discuss it with your instructor.