There's no age limit to masturbating, and children sometimes do it. It's a perfectly natural behavior, so you shouldn't feel strange or abnormal if you're doing it and exploring your body,
Also know that from a medical perspective, masturbating can actually be healthy. Health benefits include:-
- It's THE safest sex there is. You cannot give yourself any STDs, and there's no risk of an unwanted pregnancy from masturbating (though there is a slight risk with mutual masturbation if you touch someone else's genitals and then your own.)
- in girls and women, it helps to relieve PMS symptoms, like moodiness and crabbiness
- in girls and women, it relieves menstrual pain
- boosts your mood
- relieves stress
- increases your immunity
- relieves tension
- you're familiarizing yourself with your body, so you can detect any changes which may indicate a health problem sooner
- relieves anxiety
- it's a safe euphoria, without the use of recreational drugs or alcohol
The only time when it causes issues is if you're masturbating constantly to the point where you're hurting yourself, or you're unable to engage in your usual activities. If that happens, you may have a problem, in which case you need to see a doctor.
Hope this helps.