bluedemon382 wrote:The i finger locks itself if I try to play in tempo for more than a measure and there are other problems too.
If at all possible you should seek guidance from an experienced teacher.
It may be that there is a relatively
straightforward answer to your problems related to general posture and dysfunctional tension. Your brief description of a locking finger and lack of independent control doesn't immediately sound like focal dystonia - but live observation is to be recommended.
It also sounds as if you have been trying to build technique mainly through playing your chosen repertoire - rather you should spend some time developing the actual mechanical skills required through less complex routines and exercises. Again, a good teacher would be best placed to guide you.