Sorry you are having issues. My son started kindergarten this year too. I've had two issues that I contacted his teacher about, though I didn't tell my son I had contacted her. Both times the issues were resolved quickly.

I'd suggest talking to his teacher about it, either ring and leave a message to call you back or leave a note. Rather than talking to her in front of him which may upset him. I know my DS wouldn't like that either so it's quite common for them not to want to make waves. It's an issue that can be easily dealt with and hopefully she will be accommodating.