Rebegin!

[sepand]

Hi,
This is my first post in this forum, and I'm asking for some advice.
I began piano when I was 9, gave it up when I was 13 because of my bad teacher.
I can't tell how I'm sorry for that, but what's done is done.
Now I'm 24. Been practicing by myself all these years and I'm not that bad.
But what I want is to rebegin seriously...
Because of self-practice I have many problems now and I think I need your help.
First I want to ask what do you recommend me to do to begin again? (beside working with a good piano teacher!)
Another problem I have is that my left hand -unlike my right hand which moves freely- gets tense while playing, and at one point it can no longer move!
So, what you think I should do? mostly about my rebeginning process!
Thanks...