Regarding your three factors, I felt the exact same way when I was your age -- I'm 35 now. What I will say is that I regret not talking in the foreign language more. I'm a native English speaker who learned French in school, had Urdu spoken at home, and learned to read Arabic. I still remember a lot of French and wish I would have spoken it more. If it's possible, try to find someone who you can talk to in English one-on-one. Before you practice, tell them that you stutter and you are just practicing. They should understand and not laugh/judge. Learning any foreign language is hard, and even harder to practice with a stutter. It will take a lot of effort, but will definitely get easier, and you'll build more confidence. I've written about it a little here: http://helloistutter.com/2014/05/15/seventh-grade/ Hope that helps.