Bernadette,
Sorry if I sounded suspicious in my first answer. Although you may have to work hard, practice should mostly be fun. If your teacher is working with you on posture, wrist and arm position and the sort of thing you mentioned, then there is a lot of room to experiment. When the teacher shows you (or you find on your own) the correct, efficient movement for a particular scale or or particular bit from your Mozart, it should suddenly get a lot easier. It should also feel physically very pleasant.
I am a bit in the same boat as you. I started as an adult and worked my way fairly well on my own, so I knew a bit of music, but a good teacher really helped. After every lesson you should expect to be taking away ideas you can go home and experiment with. I've taken 3-4 days at a time doing nothing but hours of very slow scales focusing on all the mechanical details you mention, because my teacher had shown me something about my wrist flexibility; it can be very interesting, and it makes a big difference when you get back to playing your pieces. But you need a good teacher to be able to make the right sort of thought provoking suggestions. With the right teacher, I think you should feel a real difference within weeks.
On the other hand, training at the Moscow Conservatory does not automatically produce a great teacher, so if you feel bored and frustrated and are not progressing, the problem might be with the teacher, not you.
Bill