No, you are not allowed to use PayPal. You have to be at least 18 years of age.
Assuming you’re in the United States, then the Terms of Service of PayPal cites the following:
Welcome to PayPal!
This user agreement is a contract between you and PayPal, Inc. that governs your use of your PayPal account and the PayPal services. It applies to U.S. PayPal accounts only. For an individual to open a U.S. PayPal account and use the PayPal services, you must be a resident of the United States or one of its territories and at least 18 years old, or the age of majority in your state of residence. For a business to open a U.S. PayPal account and use the PayPal services, the business must be organized in, operating in, or resident of, the United States or one of its territories.