It is illegal for the school to treat you unfairly or harass you because you are pregnant or have a child.
It is also against the law for you to be treated unfairly because of your
- sexual identity, or
- sexual orientation
Talk to your school counselor or another adult if you are being treated unfairly for any reason.
If the problem does not go away, call a lawyer. The lawyer will help you no matter how old you are. Find legal help here.