MS is hard for almost every kid even if they are just going to the next school in their neighborhood. I'd give it a few more months for your child to settle in.
Our MS can be rough with swearing, pushing, fights and it's in a wealthy area so I think is just you and your child not really understanding what public school is like in general. I don't really know but my guess is that your child's classmates are no more abrasive than any others.