Hello, i feel i have excessively masterbated since i was 13. i would do it about everyday - 3 times max. but i would also have some breaks. i'm 18 yea?

Probably OK: There is no known frequency of masturbation that is unhealthy. Masturbation is considered normal and even healthy, unless you are unable to not do so in inappropriate settings, such as in public places, or while in a relationship, although, even then, only if it causes problems in the relationship. However, pornography can be a problem, as it tends to present a distorted view of sexuality.

Getting in your way?: If your masturbation is preventing you from living your life, i.e., cannot work, go to school, have relationships with other people, etc., it's worth examining with a counselor. There isn't a "legal limit," however! When you say you "feel you have excessively masturbated," it makes me think you are uncomfortable with the behavior - another reason to talk with someone further. You're probably fine!