Indeed it is totally normal. It's a totally normal part of sexual exploration, and believe me, people do it, so you shouldn't feel weird or abnormal if you're masturbating and exploring your body.
From a medical perspective, not only is masturbation normal, it can also be very healthy. The health benefits of female masturbation are:-
- THE safest sex there is. You cannot give yourself any STDs, or get yourself pregnant from masturbating (though there is a slight risk with mutual masturbation if you touch someone else's genitals and then your own.)
- helps to relieve PMS symptoms, like moodiness and crabbiness
- 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
- is 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.