I sometimes stim less when I'm sick, other times more or the same, it depends on the kind of sick really.
When I was at the hospital recently (and coming in and out of delirium) I stimmed less in terms of repetitive movements (although I think I was thrashing around a lot so maybe not), but was way more attached to grabbing onto hard objects for sensory stability than usual. I had to be pried off of the bedrails at one point for an ultrasound exam, because my senses were going haywire and I was grabbing onto the rail as the only physically stable thing in this sea of nonsensical and very soft input that I felt like I was drowning in. I also grabbed onto the puke bucket and wouldn't let go for the same reason.
I really hated whenever I was made to let go of those things, because I could not maintain any kind of cognitive stability otherwise, and then I'd get seasick from all the moving and changing things and start vomiting.
So I guess instead of my usual forms of stimming I was way more into "grab hard object and don't let go", whereas normally, while I do that, it's not so intense unless I'm extremely overloaded.
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"In my world it's a place of patterns and feel. In my world it's a haven for what is real. It's my world, nobody can steal it, but people like me, we live in the shadows." -Donna Williams