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No I have not seen a physician before about it. I am not sure how long it has been like this. My current partner has alerted my attention to it. Ever since I began to masturbate (about 20 years ago) I have always had to stimulate my clitoris indirectly.
The clitoris has several thousand nerve endings and its sensitivity can certainly vary. Since you have always been sensitive, I don't think there is a problem that needs to be treated medically. You can discuss this with your gynecologist who can confirm the appearance and size is indeed normal and there are no masses, discharge accumulation, or abnormal skin appearance near or within the clitoris.