From my autistic view, stimming is something mentally delicious.
It reduces stress and soothes when things are straining. Being wrapped in a lot of cotton fabrics is an intense and very comforting way of stimming - at least for me.
The day Sherlock went to Buckingham Palace, he seemed already 'wound up', hints are his tense posture and his unnerved comments. Maybe the ongoing presence of the client in the flat added to Sherlock's distress.
While in the palace, Sherlock stims and tries to sense his body's boundaries in several other ways, for example the movement of his toes, the way he clutches the sheet to his body and has it tightly wrapped around his upper legs. When John arrives, his presence relaxes Sherlock, as does the laughing.
Another prompt from @bluebellofbakerstreet 's wonderful Prompt List for Inktober 2019.
The reference picture I used is an edit made by @221b-carefulwhatyouwishfor, many thanks for the permission to use it :)
White gel pen on black paper, A4
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