You dont mention if you are naturally two footed. A lot of young kids struggle with this and when I was young my dad got me to hop 25 yards at a time on just one leg ( my weaker left leg). He got me to do this for about a 15 minute spell, after this I was completely knackered.
As the weeks went by its surprizing how strong my weaker leg became and how much more confidence this gave me.
During this time I didnt kick a ball with my left leg, just built the strength up.
You'll be surprised yourself after a few weeks - enjoy your training and general fitness and dont overdo it. Good luck with your footy!