[Rivière]

I have that same problem!

Whenever I get anxious, stressed, or start to feel agitated, I run my fingers through my hair. If I feel anything out of the ordinary I unconsciously start picking at it to the point I've ended up making my scalp dry. Sometimes I've scratched so much I've caused lumps to occur, which I'd then scratch and cause to bleed.

Using shampoos sort of help retain scalp moisture and ease any dryness, but it won't fix the picking.

I usually keep a pen nearby so I can play with it. One of those clicky ones, that way I can click it and flip it around rather than scratching. It doesn't work all the time, but making a conscious effort to be aware of what your hands are doing and where you're putting them is the bigger aim. The more you make yourself aware of what you're doing, the more you can help push yourself to control your urges to scratch.