Unawarebrah
1-800-OMG-STFU
It's perfectly healthy until it gets to the point were you might be using it as a crutch. If you find yourself losing interest in a social life, not interested in dating, developing low energy, not performing as well in school or work, and developing a general malaise overall, you may want to think about talking to a sexual therapist to see if you might have an addiction.
Masturbation can cause similar temporary chemical changes/imbalances in the body to drinking alcohol or taking drugs, so an addiction to it is not impossible.
Just be aware of that.
Is fapping once a week considered too many?
Well are you not interested in dating? Actively looking forward to your mastrubation sessions and planning them in advance? Do you avoid friends in order to spend time mastrubating? Are your school and/or work performances suffering lately? Do you feel constantly fatigued, mentally fogged, or just uninspired in general?
If so, you may want to talk to someone.
3nodding
If not, you're probably ok for now.