I'm a student teacher!!!?

I'm a stutterer student who already have taught primary students in teaching practice. I was that much afraid from my stuttering while teaching, because primary students did not notice or concentrate on this kind of thing.However, I'm now very worried because I'm going to teach secondary students and they are expected to notice and pay attention on this thing and that's may lead them to laugh at me!!!1 what can I do??? anyadive???