I don't understand why you are feeling guilty about this. It's perfectly normal. Actually I would say it wouldn't be normal if you didn't. Everybody on this planet no matter what age, or sex thinks about sex, and a lot of people please themselves as you are doing. There is no harm in doing it. If you feel embarrassed then, there's no need to, because it's a personal/ private thing. Nobody else needs to know about it. But if it's really bothering you that much then try your best to control yourself. For example every time you feel like fingering yourself go get some gum or and food and chew on it instead. Honestly sweetie don't worry about it. What you're doing is fine.
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