Denim (actually, any scratchy material, but denim is the worst)
Being touched on my head or shoulders/being touched unexpectedly
Loud noise
In particular, the sounds of people walking, pouring/drinking liquids, hand dryers, whistling, and opening/closing doors.
Having my hands sticky
Gloves, mittens, and scarves
One or a few things out of place somewhere when everything else there is organised
Noticing grammatical errors (even my own)
Sometimes, the sight of something will make me think of how it feels, like when I see someone wearing denim or touching someone else's shoulders, so I hate that too.
The smell of deodorant
Brushing my hair/teeth