I have read about this, and it is AS related. I have the same problem to some extent. If I am not holding something in my hands, then I am doing something with them! I carry around plastic toys and books, and they all have a special spot as well. It's sort of like a stim, in a way. It definitely helps me feel more grounded. 
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Hi! I'm Stampy (not the actual YouTuber, just a fan!) and I have been diagnosed professionally with ASD and OCD and likely have TS. If you have any questions or just want to talk, please feel free to PM me!
Current Interests: Stampy Cat, AGT, and Medicine