Sadly, in most states if you call the police because your parents are fighting, there is a good chance that at least one of them will be going to jail. That does not necessarily mean you should not call, but you should understand the potential ramifications before you take any action. Speak to an adult that you can trust. Be careful of who you select since people in positions such as teachers and medical personal may be required by law to report issues of some forms of abuse. A clergy member or family member are good options.
Domestic violence is violence. You need to discuss your situation with a trusted adult counselor or advisor. If your home is not a safe environment, it needs to change. You are not responsible for your parents' behavior. An adult may have access to resources that may not involve law enforcement, at least not at the outset. On the other hand, your safety is the most important thing and you need to take all appropriate steps to protect yourself.
This is not a substitute for a consultation with a family law attorney or domestic violence counselor.