have you ever tried meditation balls??? They are a really cool stim toy that is very relaxing, and if you do it right, the bells inside the balls start making very peaceful music. They are believed by the ancient asians to promote longjevity and physical healthiness. If you dont know what they are, they are metal or jade balls (2) and you turn them around and around in the palm of your hand. You have to get the right size for your hand, usually come in 3 sizes, small, med, and large. They usually have small balls inside of them that make music when turned fast enough. It makes a whirling jingle sound. Both the sound and the motion on the hands is very relaxing. That would be a really good replacement for biting your finger or pulling your eyebrows so you can replace a self injurious stim with a self-healing one. I am also prone to self injurious behavior, but usually not as a stim, only during a major meltdown.
But as far as the nerve thing goes, go ask your doctor about that...I think all the fingers are connected together as far as nerves go. No you wont die from it, but it can effect your physical functioning if you injure a nerve in your hand, expecially if you are right handed.
I broke my right hand once and I am very right handed...I was very disabled for about 6 weeks. I cant do squat with my left hand and I was in college when I did that. If you have to know I broke my hand punching an inflatable bed that I thought was fully inflated when it was not, my hand it the concrete floor below. Why did I do that? because my art teacher was evil and he loved to test on trivial crap and I studied for what was important...or at least I thought so. Anyway, sorry about the rant
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All art is a kind of confession, more or less oblique. All artists, if they are to survive, are forced, at last, to tell the whole story; to vomit the anguish up.
-James Baldwin