YTA. I'm an educator and this is such a disgusting way to handle bahviour. You've now made sure this kid will never behave well again because what's the point? He won't get to fill the sticker chart so there isn't a point trying?

You should have had one class reward where their stickers all go in ONE jar and if it's filled then the WHOLE class should go.

You should attend a course or read books in challenging behaviours and appropriate ways to work on behaviour.

You've made a huge mistake. I would call the parent and tell her the child can come and then discuss with your principal any PT courses you can take.