Some secondary schools have counsellors who are there to help you with any problems or issues you might be having. Your problems don’t necessarily need to be related to school. Some schools also have school nurses who are skilled at dealing with a range of health issues.
Universities and colleges will often have health services, which includes counselling for students. These are generally located in student health centre and are free of charge.
You may want to ask a teacher or someone at your school about what’s available for you.