Normally the introduction part is the first like ~20 minutes of the lesson so maybe arrive in late and just say there was traffic or something? Or you could pretend to be sick in the nurses office until it's been about 20 minutes then go to class and hope everyone's introduced yourselves, could work unless the teacher asks you to introduce yourself, but if the teacher is already in her lessons she may just decided to carry on so she doesn't lose where she's at (dunno why i assumed u have girl teacher lol haha). Hope things work out and I hope you try this cause it's better than skipping the whole class or something. LMK how it goes please. I was so scared heading into high school/secondary school like 10 years ago so I know exactly how you feel, i stuttered through my introduction and got through it and thankfully no one laughed or judged for it, so think positive. :)